Lower dosage strength pharmaceutical compositions forumlated with 3.75% imiquimod

ABSTRACT

Pharmaceutical formulations and methods for the topical or transdermal delivery of 1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine or 1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine, i.e., imiquimod, to treat actinic keratosis with short durations of therapy, than currently prescribed for the commercially available Aldara® 5% imiquimod cream, as now approved by the U.S. Food &amp; Drug Administration (“FDA”), are disclosed and described. More specifically, lower dosage strength imiquimod formulations to deliver an efficacious dose of imiquimod for treating actinic keratosis with an acceptable safety profile and dosing regimens that are short and more convenient for patient use than the dosing regimen currently approved by the U.S. Food &amp; Drug Administration (“FDA”) for Aldara® 5% imiquimod cream to treat actinic keratosis are also disclosed and described.

This application is a continuation of copending U.S. application Ser.No. 12/636,613, filed Dec. 11, 2009, which application claims thebenefit of U.S. Provisional Application Ser. No. 61/205,145 filed Jan.15, 2009, U.S. Provisional Application Ser. No. 61/144,731 filed Jan.14, 2009, U.S. Provisional Application Ser. No. 61/139, 536 filed Dec.19, 2008, the teaching of all of which are incorporated herein byreference.

FIELD OF THE INVENTION

The present invention relates to pharmaceutical formulations and methodsfor the topical or transdermal delivery of1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine, also known as (aka)1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine, aka imiquimod, totreat actinic keratosis with shorter durations of therapy, thancurrently prescribed for the commercially available Aldara® 5% imiquimodcream, as now approved by the U.S. Food & Drug Administration (“FDA”).More specifically, the present invention is directed to lower dosagestrength imiquimod formulations to deliver an efficacious dose fortreating actinic keratosis with an acceptable safety profile, but with adosing regimen that is shorter and more convenient for patient use thanthe dosing regimen currently approved by the FDA for Aldara® 5%imiquimod cream.

BACKGROUND

Actinic keratosis (AKs) is a precancerous (premalignant) skin disordercaused by or associated with chronic exposure to radiant energy, such assunlight. Actinic keratosis lesions are small, red, rough spots orlesions occurring on sun exposed areas of the skin. Actinic keratosislesions possess many of the same cellular changes observed in a skincancer called squamous cell carcinoma (SCC). Research shows that amutated version of the p53 gene is found in sun-damaged cells in thebody and is present in more than about 90% of people who have AKs andsquamous cell carcinomas. Although most actinic keratosis lesions do notactually become cancerous, some lesions can become malignant.

It is believed that actinic keratosis develops in skin cells called“keratinocytes”, which are the cells that constitute about 90% of theepidermis, the outermost layer of skin. Chronic sun exposure, over time,generates mutations in these cells and causes the cells to change insize, shape, the way they are organized, and the way they behave. Inaddition, the cellular damage can even extend to the dermis, the layerof skin beneath the epidermis.

Actinic keratosis lesions generally measure in size between about 2 toabout 6 millimeters in diameter, AK lesions can range in color fromskin-toned to reddish and often have a white scale on top. On occasion,AK lesions will form into the shape of animal horns. When this occurs,the AKs are known as “cutaneous horns.”

People who are at higher risk for developing actinic keratosis tend tobe fair-skinned and spend significant time outdoors, e.g., at work or atplay, over the course of many years. AK lesions usually develop on thoseareas of the body that have been constantly exposed to the sun foryears. Additionally, the skin often becomes wrinkled, mottled, anddiscolored from chronic sun exposure. Common locations for actinickeratosis include the face, ears, lips, balding scalp, back of the neck,upper chest, the tops of the hands and forearms. When AK lesions developon the lips, the condition is known as actinic cheilitis. Actiniccheilitis can be characterized by a diffuse scaling on the lower lipthat cracks and dries. In some cases, the lips will have a whitishdiscoloration on the thickened lip.

Actinic keratosis is generally more common after age 40, because actinickeratosis take years to develop. However, even younger adults maydevelop actinic keratosis when living in geographic areas that areexposed to high-intensity sunlight year round, such as Florida andSouthern California.

Actinic keratosis has become a significant health care issue in theUnited States of America. It is estimated that over 20 million Americanssuffer from actinic keratosis, and that that number continues to grow.In fact, actinic keratosis is so common today that treatment for actinickeratosis ranks as one of the most frequent reasons people consult adermatologist.

The compound characterized as1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine or1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine, and known asimiquimod, is disclosed in U.S. Pat. No. 4,689,338 and described thereinas an antiviral agent and as an interferon inducer, which isincorporated herein by reference in its entirety. A variety offormulations for topical administration of imiquimod are also describedtherein. This U.S. Pat. No. 4,689,338 is incorporated herein byreference in its entirety.

U.S. Pat. No. 4,751,087 discloses the use of a combination of ethyloleate and glyceryl monolaurate as a skin penetration enhancer fornitroglycerin, with all three components being contained in the adhesivelayer of a transdermal patch, wherein this U.S. patent is incorporatedherein by reference in its entirety.

U.S. Pat. No. 4,411,893 discloses the use ofN,N-dimethyldodecylamine-N-oxide as a skin penetration enhancer inaqueous systems, wherein this U.S. patent is incorporated herein byreference in its entirety.

U.S. Pat. No. 4,722,941 discloses readily absorbable pharmaceuticalcompositions that comprise a pharmacologically active agent distributedin a vehicle comprising an absorption-enhancing amount of at least onefatty acid containing 6 to 12 carbon atoms and optionally a fatty acidmonoglyceride. Such compositions are said to be particularly useful forincreasing the absorption of pharmacologically active bases, whereinthis U.S. patent is incorporated herein by reference in its entirety.

U.S. Pat. No. 4,746,515 discloses a method of using glyceryl monolaurateto enhance the transdermal flux of a transdermally deliverable drugthrough intact skin, wherein this U.S. patent is incorporated herein byreference in its entirety.

U.S. Pat. No. 5,238,944, U.S. Pat. No. 7,038,051, U.S. Pat. No.6,693,113, U.S. Pat. No. 6,894,060 U.S. Patent Publication No.2007/0123558, U.S. Patent Publication No. 2004/087614, U.S. PatentPublication No. 2002/147210, and WO2008US53522 disclose topicalformulations and/or topical and transdermal delivery systems containing1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine or1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine, wherein each areincorporated herein by reference in their entireties.

Currently, the FDA has approved a 5% imiquimod cream, commerciallyavailable under the brand name Aldara®, to treat certain dermal andmucosal associated conditions, such as (1) the topical treatment ofclinically typical, nonhyperkeratotic actinic keratosis (AK) on the faceor scalp in immunocompetent adults, (2) topical treatment ofbiopsy-confirmed, primary superficial basal cell carcinoma (sBCC) inimmunocompetent adults, and (3) the topical treatment of externalgenital and perianal warts/condyloma acuminate in patients 12 years orolder.

Aldara® is the brand name for an FDA-approved 5% imiquimod cream, whichis an immune response modifier. Each gram of the Aldara® 5% imiquimodcream contains 50 mg of imiquimod in an off-white oil-in-water vanishingcream base consisting of isostearic acid, cetyl alcohol, stearylalcohol, white petrolatum, polysorbate 60, sorbitan monostearate,glycerin, xanthan gum, purified water, benzyl alcohol, methylparaben,and propylparaben. The Aldara® 5% imiquimod cream is packaged insingle-use packets or sachets, each containing 250 mg of cream,equivalent to 12.5 mg of imiquimod.

Chemically, imiquimod, as indicated above, is known as1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine or1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine. Imiquimod has a molecularformula of C₁₄H₁₆N₄ and a molecular weight of 240.3. The chemicalstructural formula for imiquimod is as follows:

Notwithstanding FDA approval, Aldara® 5% imiquimod cream treatment isnot without limitation, including an unsimplified and lengthy dosingregimen. Generally speaking, the treatment regimen for actinic keratosisusing FDA-approved Aldara® 5% imiquimod cream consists of applying theAldara® 5% imiquimod cream two times per week for a full 16 weeks to adefined/limited treatment area on the face or scalp (but not bothconcurrently). The surface treatment area for Aldara® 5% imiquimod creamis limited to approximately 25 cm² (e.g., a 5 cm×5 cm area, which may beof any shape; the treatment area does not have to be square) and isdefined as one contiguous area. The number of AK lesions treated withAldara® 5% imiquimod cream per treatment area is generally between about4 and about 8. Because the treatment area is quite small, less than onesingle-use Aldara® packet or sachet (250 mg of total cream, of which12.5 mg is imiquimod) is generally used per application. Inconsistenciesin both compliance and therapeutic results frequently occur with thetreatment of actinic keratosis with FDA-approved Aldara® 5% imiquimodcream due to the lengthy treatment period, i.e., 16 weeks, thecomplicated dosing regimen, i.e., twice weekly, and the high incidenceof application site reactions.

Subsequent to FDA-approval of Aldara® 5% imiquimod cream to treatactinic keratosis, a pilot study was conducted that was an open-labeltrial that included 25 patients who had between 5 and 20 discrete AKswithin a cosmetic unit of the forehead, scalp, or cheek. During thispilot study, treatment consisted of once-daily application of 5%imiquimod cream, three times a week for four weeks to the entirecosmetic unit, followed by a rest period of four weeks. The cycle wasrepeated if any AKs remained after a complete eight-week cycle. Amaximum of three cycles was permitted (24 weeks). Thirty-three sites(i.e., cosmetic units) in 25 subjects were evaluated. According to theauthors, compliance was excellent with a very tolerable safety profile.Complete clearing of all AKs was noted in 82% (27/33) of anatomic sitesin 25 study subjects. Almost half the sites (15/33) were clear at theend of the first cycle. A “therapeutic interval” was noted during therest period wherein clinical inflammation subsided but AKs continued toclear. An added effect, according to the authors, was the uncovering andclinical appearance and subsequent eradication of incipient(subclinical) AKs in the treatment area. As a result, the authorsconcluded that there was excellent compliance with the cycle therapyregimen utilized in this study and that the identification of atherapeutic interval may prove to be beneficial in formulatingindividualized dosing regimens. The authors warned, however, that thefindings of the study must be evaluated cautiously. The authors alsocautioned that, because this study was an open-label trial in a smallnumber of study subjects, safety, efficacy and duration of efficacyneeds to be corroborated by controlled, randomized trials with largerstudy populations. See Salasche S. J., Levine N., and Morrison L.: Cycletherapy of actinic keratoses of the face and scalp with 5% topicalimiquimod cream: An open-label trial. J Am Acad Dermatol. 47(4):571-7(October 2002).

Also subsequent to FDA-approval of Aldara® 5% imiquimod cream to treatactinic keratosis, a dual-center, randomized, double-blind,vehicle-controlled study was conducted to evaluate the safety andefficacy of short courses of therapy with Aldara® 5% imiquimod cream inclearing ≧75% of baseline solar keratoses (“SK”) within a field oftreatment. Subjects with 5-15 baseline SK within one treatment area(scalp, forehead and temples, or both cheeks) were randomized to applyimiquimod or vehicle cream to the entire treatment area three times aweek for 3 weeks. Subjects were assessed 4 weeks after completing thefirst course for clearance of lesions. Subjects with <75% clearance werecommenced on a second 3-week course of study cream. Subjects with ≧75%clearance were followed up until study completion without furthertherapy. All subjects were evaluated at the study endpoint of 14 weeksafter initiating therapy for assessment of the primary outcome (≧75%clearance of baseline solar keratoses). According to the authors,twenty-one out of 29 (72%) imiquimod-treated subjects cleared ≧75% ofbaseline lesions compared with 3/10 (30%) subjects using the vehiclecream (Fisher's exact test, P=0.027) and the imiquimod was welltolerated. Also according to the authors, the results of this studysuggest that 5% imiquimod administered three times per week may offer atherapeutic alternative to patients with SK on the face, and scalp, andthat one or two short courses may be an alternative to the continuouslonger Aldara® 5% imiquimod cream therapy approved by the FDA. Theauthors did caution, however, that, because the study had a relativelyshort follow-up endpoint, additional studies may be needed to evaluateif the therapeutic outcome can be sustained. See Chen K. et al.: LinksShort-course therapy with imiquimod 5% cream for solar keratoses: arandomized controlled trial. Australasian J Dermatol. 44(4):250-5(November 2005).

In addition, a multi-center, vehicle-controlled, double-blind study toassess the safety and efficacy of imiquimod 5% cream applied once daily3 days per week in one or two courses of treatment of actinic keratoseson the head was conducted and reported in 2007. According to theauthors, a total of 259 patients diagnosed with AK were enrolled intwenty study centers in Europe and applied imiquimod for 4 weeks,entered a 4-week rest period and if they did not have completeclearance, the patients then entered a second course of treatment. Thearea of treatment was confined to about 25 cm². As reported by theauthors, patients in the imiquimod group had an overall completeclearance rate of 55.0% (71/129) vs. a rate of 2.3% (3/130) for thevehicle group and that there was a high rate of agreement between theclinical assessment and histological findings with respect to AK lesionclearance. The authors further reported that, at both 8-weekpost-treatment visits, the negative predictive value of the investigatorassessment was 92.2% for clinical assessments vs. histological results.The authors concluded that a 4-week course of treatment with three timesweekly dosing of imiquimod 5% cream, with a repeated course of treatmentfor those patients who fail to clear after the first course oftreatment, is a safe and effective treatment for AK, and the overallcomplete clearance rate (complete clearance after either course 1 orcourse 2) is comparable to the 16-week Aldara® 5% imiquimod creamtreatment regimen, while decreasing drug exposure to the patient anddecreasing the overall treatment time. See Alomar, A., J. Bichel, etal.: Vehicle-controlled, randomized, double-blind study to assess safetyand efficacy of imiquimod 5% cream applied once daily 3 days per week inone or two courses of treatment of actinic keratoses on the head.British Journal of Dermatology. 157(1): 133-41 (2007).

Another vehicle-controlled, double-blind, randomized study of imiquimod5% cream applied 3 days per week in one or two courses of treatment foractinic keratoses on the head was conducted and also reported in 2007.According to the authors, patients with actinic keratosis lesions on thehead applied imiquimod or vehicle cream 3×/wk for 4 weeks (course 1),patients with remaining lesions received another course of treatment,and complete and partial clearance rates were evaluated after course 1,after course 2 (overall), and 1 year later. The authors concluded thatimiquimod 3×/wk in one or two courses of treatment appears to beeffective for the treatment of actinic keratoses on the head, providinglong-term clinical benefits and that some recurrences do occur, solong-term follow-up is recommended. See Jorizzo, J., S. Dinehart, etal.: Vehicle-controlled, double-blind, randomized study of imiquimod 5%cream applied 3 days per week in one or two courses of treatment foractinic keratoses on the head. Journal of the American Academy ofDermatology. 57(2): 265-8 (2007).

Another multicenter, open-label study using imiquimod 5% cream in one ortwo 4-week courses of treatment for multiple actinic keratoses on thehead was conducted and also reported in 2007. According to the authors,this was an open-label, phase IIIb study involving 180 dermatologyclinics and practices in Germany, and patients were eligible if they hadclinically typical, visible AK lesions located anywhere on the head,excluding the upper and lower eyelids, nostrils, lip vermilion, andinside the ears. The authors reported that patients applied imiquimodstudy cream to the treatment area once daily 3×/week for 4 weeks(course 1) followed by a 4-week post treatment period and that patientswith AK lesions remaining in the treatment area underwent a second4-week treatment course. Apparently, the treatment area was notrestricted and patients were allowed to use one or two sachets perapplication. The size of the treatment areas and number of sachetsapplied were not reported. The median number of AK lesions at baselinewas 7. The authors further reported that 829 patients entered the studyand that, overall, the complete clearance rate was 68.9% (571/829), thepartial clearance rate (percentage of patients with ≧75% reduction inthe number of baseline AK lesions) was 80.2%. The authors acknowledgedthat local skin reactions (LSRs) and application site reactions (ASRs)were the most commonly reported adverse events, and that four patientsdiscontinued from the study due to LSRs or ASRs. The authors concludedthat a shorter treatment regimen of imiquimod 5% cream, i.e., once daily3×/week for 4 weeks for 1 or two courses, can produce complete clearancerates similar to those seen with 16 weeks of Aldara® 5% imiquimod creamtreatment and has the advantage of lower drug exposure, resulting in abetter benefit-risk profile for the patient. See Stockfleth, E., W.Sterry, et al.: Multicentre, open-label study using imiquimod 5% creamin one or two 4-week courses of treatment for multiple actinic keratoseson the head. British Journal of Dermatology. 157 Suppl 2: 41-6 (2007).

Another randomized study of topical 5% imiquimod vs. topical5-fluorouracil vs. cryosurgery in immunocompetent patients with actinickeratoses, including a comparison of clinical and histological outcomesincluding 1-year follow-up, was conducted. According to the authors,this study compared the initial and 12-month clinical clearance,histological clearance, and cosmetic outcomes of topically applied 5%imiquimod (IMIQ) cream, 5% 5-fluorouracil (5-FU) ointment andcryosurgery for the treatment of AK of patients who were randomized toone of the following three treatment groups: one or two courses ofcryosurgery (20-40 seconds per lesion), topical 5-FU (twice daily for 4weeks), or one or two courses of topical imiquimod (three times per weekfor 4 weeks each). In this study, the treatment area was confined to oneanatomic area of 50 cm² or less. The authors reported that: (1)sixty-eight percent (17/25) of patients treated with cryosurgery, 96%(23/24) of patients treated with 5-FU, and 85% (22/26) of patientstreated with IMIQ achieved initial clinical clearance, P=0.03; (2) thehistological clearance rate for cryosurgery was 32% (8/25), 67% (16/24)for 5-FU, and 73% (19/26) in the imiquimod group, P=0.03; (3) the12-month follow-up showed a high rate of recurrent and new lesions inthe 5-FU and cryosurgery arms; (4) the sustained clearance rate ofinitially cleared individual lesions was 28% (7/25) for cryosurgery, 54%(13/24) for 5-FU and 73% (19/26) for imiquimod (p<0.01); (5) sustainedclearance of the total treatment field was 4% (1/25), 33% (8/24), and73% (19/26) of patients after cryosurgery, 5-FU, and imiquimod,respectively (P<0.01); and (6) the patients in the imiquimod group werejudged to have the best cosmetic outcomes (P=0.0001). The authorsconcluded that imiquimod treatment of AK resulted in superior sustainedclearance and cosmetic outcomes compared with cryosurgery and 5-FU andthat imiquimod should be considered as a first line therapy forsustained treatment of AK. See Krawtchenko, N., J. Roewert-Huber, etal.: A randomized study of topical 5% imiquimod vs. topical5-fluorouracil vs. cryosurgery in immunocompetent patients with actinickeratoses: a comparison of clinical and histological outcomes including1-year follow-up. British Journal of Dermatology. 157 Suppl 2: 34-40(2007).

Also subsequent to FDA-approval of Aldara® 5% imiquimod cream to treatactinic keratosis, an open-label study to assess the safety and efficacyof imiquimod 5% cream applied once daily three times per week in cyclesfor treatment of actinic keratoses on the head was conducted. Duringthis open-label study, imiquimod 5% cream was administered three timesper week for four weeks followed by four weeks of rest (cycle 1) to AKlesions on the head. If AK lesions remained visible at the end of cycle1, a second treatment cycle was instituted. According to the authors,50% (30 of 60) of the subjects who experienced complete clearance of AKlesions, and 75% (30 of 40) of the subjects who experienced partialclearance of AK lesions after imiquimod treatment at the end of cycle 2.The authors further reported that 77% of the subjects, who achievedcomplete clearance, had no visible AK lesions 12 weeks post-treatmentand that the imiquimod was well tolerated. The authors concluded that 5%Imiquimod cycle therapy, when administered three time per week for fourweeks followed by four weeks of rest (cycle 1) combined with a secondtreatment cycle repeat, may be a safe and effective alternative tocontinuous imiquimod therapy for the treatment of AK lesions. Theauthors cautioned, however, that while cycle therapy does not affect theshort-term AK recurrence rate, long-term follow-up is required. Theauthors also cautioned that further randomized, vehicle-controlledtrials are needed. See Rivers J. K. et al.: Open-label study to assessthe safety and efficacy of imiquimod 5% cream applied once daily threetimes per week in cycles for treatment of actinic keratoses on the head.J Cutan Med Surg. 12(3):97-101 (May-June 2008).

In view of the above, there is a need for improved actinic keratosistopical treatment that overcomes the current limitations associated withthe current FDA-approved topical treatment regimen for actinickeratosis, i.e., 16 weeks, twice per week, with FDA-approved Aldara® 5%imiquimod cream.

SUMMARY OF THE INVENTION

The present invention overcomes the above-mentioned limitationsassociated with the treatment of actinic keratosis with FDA-approvedAldara® 5% imiquimod cream through the discovery of novel and improvedimiquimod treatment regimens of short duration, lower dosage strengthimiquimod pharmaceutical formulations, and simplified dosing regimens totreat actinic keratosis.

Generally speaking, the present invention provides for new and improvedsubstantially less-irritating lower dosage strength imiquimodpharmaceutical formulations, which are suitable for daily application inconnection with substantially condensed treatment regimens andsubstantially expanded treatment areas, for topical and/or transdermaladministration of an effective amount of imiquimod to treat subjects whoare diagnosed with clinically typical, nonhyperkeratotic actinickeratosis (AK), preferably on the face or balding scalp ofimmunocompetent patients. In addition, the present invention providesfor new and improved actinic keratosis treatments, wherein: (1)treatment periods of the present invention are substantially shorter induration, i.e., up to six weeks and preferably up to four weeks, thanthe current FDA-approved 16-week treatment regimen for actinic keratosistreatment; (2) dosing regimens of the present invention aresubstantially simpler, i.e., one application daily each day for up tosix weeks and preferably up to four weeks, than the current dosingregimen, i.e., once-a-day but only twice per week for 16 weeks, for thecurrent FDA-approved Aldara® 5% imiquimod cream for actinic keratosistreatment; (3) treatment areas of the present invention aresubstantially larger, i.e., up to about 250 cm², than the currentFDA-approved treatment area, i.e., up to about 25 cm², for Aldara® 5%imiquimod cream for actinic keratosis treatment; (4) number of AKlesions being treated in accordance with the present invention aresubstantially greater in number, i.e., between about 5 and about 20 ormore AK lesions per treatment area, than the number of AK lesions, i.e.,between about 4 and about 8 AK lesions per treatment area, generallybeing treated with the current FDA-approved Aldara® 5% imiquimod creamfor actinic keratosis treatment; (5) less-irritating imiquimodpharmaceutical formulations of the present invention are formulated witha lower dosage strength, i.e., between about 1% and about 4.25%imiquimod, than the current FDA-approved Aldara® 5% imiquimod cream foractinic keratosis treatment; and (6) lower subject incidence ofapplication site reactions is experienced in accordance with the presentinvention, as compared with higher subject incidence of application sitereactions experienced with the current FDA-approved Aldara® 5% imiquimodcream and treatment regimen for actinic keratosis treatment.

In other words, the present invention provides for new and improvedactinic keratosis treatments that cover larger treatment areas, haveshort durations of therapies, use lower imiquimod dosage strengths, havesimplified daily dosing regimens, and have a lower incidence ofapplication site reactions, as compared to treatment of actinickeratosis with Aldara® 5% imiquimod cream, as currently approved by theFDA.

The present invention thus provides numerous surprising advantages overcurrent FDA-approved Aldara® 5% imiquimod cream therapy for actinickeratosis treatment. For example, the present invention provides for (1)an expanded imiquimod treatment area estimated to be approximately200-250 cm², e.g., the full face or entire balding scalp, (2) ashortened treatment regimen, i.e., up to about 6 weeks and preferably upto about 4 weeks, (3) a simplified dosing regimen, i.e., once daily oneach day of the treatment period, (4) low systemic imiquimod bloodlevels even though the treatment area is vastly expanded and the dosingfrequency is increased, (5) treatment of an increased number of clinicallesions per treatment period, e.g., about 5 to about 20 AK lesions ormore, and (6) a lower subject incidence of application site reactions,even though there is an increase in imiquimod surface area penetrationdue to the expanded treatment area and increased applied amounts inaccordance with the present invention, during the topical treatmentregimen of actinic keratosis, than currently associated withFDA-approved Aldara® 5% imiquimod cream therapy.

Thus, the present invention overcomes certain of the limitationsassociated with the treatment of actinic keratosis with FDA-approvedAldara® 5% imiquimod cream and addresses current medical needs for (1) alarger treatment area (full face or balding scalp: >25 cm² vs. up to 25cm² for Aldara® 5% imiquimod cream), (2) a shorter treatment period,e.g., two 2-week or two 3-week treatment cycles with an interim 2-weekor 3-week no-treatment period sandwiched between them, respectively, vs.the full 16-week treatment regimen for Aldara® 5% imiquimod cream), (3)a more intuitive dosing regimen (daily dosing vs. twice weekly dosingfor Aldara® 5% imiquimod cream) and (4) less or a lower incidence ofapplication site reactions.

The less-irritating lower dosage strength imiquimod pharmaceuticalformulations of the present invention may comprise:

a) a lower dosage strength of1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine or1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine (imiquimod) fordelivering an effective amount of imiquimod; and

b) a pharmaceutically acceptable vehicle for imiquimod, which vehiclecomprises a fatty acid, such as isostearic acid, palmitic acid, stearicacid, linoleic acid, unrefined oleic acid, refined oleic acid, such asSuper Refined® oleic acid NF (e.g., a highly purified oleic acid, i.e.,an oleic acid which has low polar impurities, such as peroxides, a lowperoxide value and is marketed by CRODA; see e.g., www.crodausa.com) anda combination thereof, in a total amount of about 3 percent to about 45percent by weight based on the total weight of the formulation.

The lower dosage strength imiquimod formulations of the presentinvention, especially those wherein the vehicle comprises an isostearicacid as the fatty acid, are uniquely designed to have physical andchemical stability, solubility, emollient properties and doseproportionate delivery similar to or better than Aldara® 5% imiquimodcream. More specifically, the lower dosage strength imiquimodformulations of the present invention, especially those wherein thevehicle comprises an isostearic acid as the fatty acid, are believed togenerally have similar or improved skin emolliency at the applicationsite and dose proportionate release rates as to both the release ratesof the imiquimod and the total amount of imiquimod released, relative tothe Aldara® 5% imiquimod cream. In other words, the lower dosagestrength imiquimod formulations of the present invention areconcentration influenced and have similar release rates to the Aldara®5% imiquimod cream. Additionally, the greater the amount of imiquimod inthe formulation, the faster and the greater the total amount ofimiquimod is released, evidencing that the amount in and the rate ofrelease from the formulations are imiquimod concentration dependent.Thus, while the lower dose strength imiquimod formulations of thepresent invention deliver different cumulative amounts to the stratumcorneum and epidermis, i.e., local skin delivery, than the Aldara® 5%imiquimod cream, such lower dosage strength imiquimod formulations arebelieved to have a proportional and linear relationship that is similarwith the Aldara® 5% imiquimod cream as to both the rate of imiquimodrelease and the total amount of imiquimod released and delivered locallyto the skin over time, so that the imiquimod concentrations in theformulations of the present invention, the imiquimod release rates andthe amount of imiquimod unabsorbed and delivered to the stratum corneumand epidermis, which has been released from the formulations, aregenerally proportional and linear to the Aldara® 5% imiquimod cream.

In addition, the lower dosage strength imiquimod formulations of thepresent invention, especially those wherein the vehicle comprises anisostearic acid as the fatty acid, are uniquely designed to be stableand fall within the range of the specifications for the commerciallyavailable Aldara® 5% imiquimod cream, such as to viscosity, pH, andstability, including microscopic and macroscopic stability. Morespecifically, the imiquimod present in the lower dosage strengthimiquimod formulations of the present invention, especially thosewherein the vehicle comprises an isostearic acid as the fatty acid,(monograph range: 90 to 110%) and benzyl alcohol (monograph range: 50 to105%) remain within limits at both about 25° C. and about 40° C. overabout a one month period and within limits at both about 25° C. andabout 40° C. over about a six month period. Furthermore, the lowerdosage strength imiquimod formulations of the present invention,especially those wherein the vehicle comprises an isostearic acid as thefatty acid, remain stabile for about six months at about 25° C. andabout 40° C., and also remain stable with respect to macroscopic andmicroscopic appearance, viscosity (monograph range: 2,000 to 35000 cPs)and pH (monograph range 4.0 to 5.5). In addition, the lower dosagestrength imiquimod formulations of the present invention are uniquelydesigned to meet the requirements specified in both United StatesPharmacopeia (“USP”) and the European Pharmacopeia (“EP”) as topreservative efficacy and remain free of degradation products whenstored at about 25° C./60% RH, about 30° C./65% RH and about 40° C./75%RH over about one, about two, about three and about six months andanalyzed at about 318 nm wavelength.

The present invention also contemplates lower dosage strength imiquimodformulations, that have unique pharmacokinetic profiles when used, forexample, in connection with the short durations of therapy to treatactinic keratosis in accordance with the present invention. By way ofexample, a 3.75% imiquimod lower dosage strength formulation of thepresent invention, when approximately 500 mg of such a formulation(about 18.75 mg imiquimod) or less is applied daily for 21 days to atreatment area of about 200 cm² on the face or balding scalp, achievessteady state by about week 2, e.g., between about day 8 and day 14, andprovides an in-vivo serum profile selected from the following (See FIG.54):

(a) a Day 21 T_(max) of from about 4 hours to about 16 hours andpreferably a mean T_(max) of about 7.4 hours with a standard deviation(“SD”) of about 3.5, a median T_(max) of about 9 hours and a geometricmean T_(max) of about 6.6 hours and a coefficient of variation (“CV”) ofabout 48%;

(b) a Day 21 C_(max) of from about 0.07 to about 0.6 ng/ml andpreferably a mean C_(max) of about 0.3 ng/ml with a standard deviationof about 0.16, a median C_(max) of about 0.35 and a geometric meanC_(max) of about 0.27 ng/ml and a coefficient of variation of about 49%;

(c) a Day 21 T_(1/2) of from about 9.7 to about 84 hours and preferablya mean T_(1/2) of about 29.3 hours with a standard deviation of about17, a median T_(1/2) of about 25.6 hours and a geometric mean T_(1/2) ofabout 26 hours and a coefficient of variation of about 58%;

(d) a Day 21 AUC₀₋₂₄ of from about 1.1 to about 12 ng·hr/ml andpreferably a mean AUC₀₋₂₄ of about 6 ng·hr/ml with a standard deviationof about 3, a median AUC₀₋₂₄ of about 7 ng·hr/ml and a geometric meanAUC₀₋₂₄ of about 5 ng·hr/ml and a coefficient of variation of about 52%;

(e) a Day 21 λz of from about 0.008 hr⁻¹ to about 0.07 hr⁻¹ andpreferably a mean λz of about 0.03 hr⁻¹ with a standard deviation ofabout 0.01, a median λz of about 25.6 hr⁻¹ and a geometric mean λz ofabout 0.03 hr⁻¹ and a coefficient of variation of about 49%;

(f) a Day 21 C_(min) of from about 0.06 to about 0.4 and preferably amean C_(min) of about 0.20 with an SD of about 0.11, a median C_(min) ofabout 0.19 and a geometric mean C_(min) of about 0.17 and a coefficientof variation of about 55%;

(g) at Day 14/7 (a ratio of the trough concentration at Day 14 over thetrough concentration at Day 7), a trough concentration geometric meanratio of about 1.09 with a 90% confidence interval (“CI”) within a rangeof between about 0.8 and about 1.5;

(h) at Day 21/14 (a ratio of the trough concentration at Day 21 over thetrough concentration at Day 14), a trough concentration geometric meanratio of about 1.33 with a 90% confidence interval (“CI”) within a rangeof between about 0.9 and about 1.9;

(i) at Day 22/21 (a ratio of the trough concentration at Day 22 over thetrough concentration at Day 21) a trough concentration geometric meanratio of about 0.93 with a 90% confidence interval (“CI”) within a rangeof between about 0.6 and about 1.3;

(j) a mean peak imiquimod serum concentration of about 0.323 ng/ml atDay 21;

(k) a Day 21 RAUC of from about 1 to about 7 and preferably a mean RAUCof about 4 with a standard deviation of about 2, a median RAUC of about3.5 and a geometric mean RAUC of about 3.3 and a coefficient ofvariation of about 56%;

(l) a Day 21 RC_(max) of from about 0.5 to about 5 and preferably a meanRC_(max) of about 3 with a standard deviation of about 1.5, a medianRC_(max) of about 2.7 and a geometric mean RC_(max) of about 2.4 and acoefficient of variation of about 54%;

(m) a Day 21 Lλz_(eff) of from about 0.006 hr⁻¹ to about 0.08 hr⁻¹ andpreferably a mean Lλz_(eff) of about 0.02 hr⁻¹ with a standard deviationof about 0.02, a median Lλz_(eff) of about 0.01 hr⁻¹ and a geometricmean Lλz_(eff) of about 0.16 hr⁻¹ and a coefficient of variation ofabout 97%; and

(n) a Day 21 T^(1/2) _(eff) of from about 8 hr to about 110 hr andpreferably a mean T^(1/2) _(eff) of about 55 hr with a standarddeviation of about 36, a median T^(1/2) _(eff) of about 50 hr and ageometric mean T^(1/2) _(eff) of about 42 hr⁻¹ and a coefficient ofvariation of about 66%.

In accordance with the present invention, a mean peak serumconcentration is achieved with a 3.75% lower dosage strength imiquimodformulation of Examples 23-28. More specifically, a mean peak serumconcentration of about 0.323 ng/ml is achieved with a 3.75% lower dosagestrength imiquimod formulation of Examples 23-28 after about 18.75 mg ofimiquimod is applied to a treatment area of about 200 cm² on the face orbalding scalp each day for 21 days.

In addition, the present invention contemplates lower dosage strengthformulations that are pharmaceutically equivalent, therapeuticallyequivalent, bioequivalent and/or interchangeable, regardless of themethod selected to demonstrate equivalents or bioequivalence, such asdermatopharmacokinetic and pharmacokinetic methodologies, microdialysis,in vitro and in vivo methods and/or clinical endpoints. Thus, thepresent invention contemplates lower dosage strength imiquimodformulations that are bioequivalent, pharmaceutically equivalent and/ortherapeutic equivalent, especially, 2.5% and 3.75% lower dosage strengthimiquimod formulations that are bioequivalent, pharmaceuticallyequivalent and/or therapeutically equivalent, when used daily inaccordance with the short durations of therapy of the present inventionto treat actinic keratosis, e.g., used on treatment areas, namely, fullface or balding scalp, that are between greater than about 25 cm² andabout 250 cm² on a daily basis for up to about six weeks, including the3×3×3 weeks 2-cycle treatment regimen, and preferably up to about 4weeks, including the 2×2×2 weeks 2-cycle treatment regimen.

Thus, the present invention contemplates: (a) pharmaceuticallyequivalent lower dosage strength imiquimod formulations which containthe same amount of imiquimod in the same dosage form; (b) bioequivalentlower dosage strength imiquimod formulations which are chemicallyequivalent and which, when administered to the same individuals in thesame dosage regimens, result in comparable bioavailabilities; (c)therapeutic equivalent lower dosage strength imiquimod formulationswhich, when administered to the same individuals in the same dosageregimens, provide essentially the same efficacy and/or toxicity; and (d)interchangeable lower dosage strength imiquimod formulations of thepresent invention which are pharmaceutically equivalent, bioequivalentand therapeutically equivalent.

By the term “lower dosage strength(s)”, as used herein, it refers to apharmaceutical formulation containing imiquimod in an amount of betweenabout 1.0 percent and about 4.25 percent by weight based on the totalweight of the formulation and preferably a pharmaceutical formulationcontaining imiquimod in an amount of about 2.5% or about 3.75%.

By the term “short duration(s)” of therapy, as used herein, it refers tothe daily topical application of an effective amount of imiquimod to adefined treatment area diagnosed with AK lesions for a totalon-treatment period of up to about 6 weeks, depending upon which lowerdosage strength imiquimod formulation of the present invention isselected for daily application, and more preferably a total on-treatmentperiod of up to about 4 weeks, wherein an optional defined interveningrest period (no treatment) of up to about 3 weeks, and more preferably arest period (no treatment) of up to about 2 weeks, may be taken at somepoint during the treatment period, to treat actinic keratosis. Thereby,the “short durations of therapy” may include, by way of example, a totalduration of 9 weeks (3 weeks on, 3 weeks off, 3 weeks on), and morepreferably 6 weeks (2 weeks on, 2 weeks off, 2 weeks on) from beginningof dosing to the end of dosing, inclusive of the rest period.Nevertheless, it should be understood by those versed in this art thatthe 2-cycle treatment regimens with a rest period sandwiched in betweenare preferred. In addition, the “short durations” of therapy may alsoinclude an 8 week examination period (no further treatment) followingthe treatment period.

The term “short duration(s)” of therapy of the present invention alsorefers to a two-cycle treatment regimen that involves either a 4-week or6-week treatment regimen, wherein each treatment cycle consists of twoor three weeks of once-daily applications of an effective amount ofimiquimod, for each day of the cycle, separated by a 2-week or 3-weekno-treatment period, respectively, such as follows:

(a) applying an effective amount of imiquimod to a treatment areaaffected with actinic keratosis once per day for fourteen (14)consecutive days or 2 weeks (cycle 1-treatment on), followed by noapplication for fourteen (14) days or 2 weeks (treatment off), followedby again applying an effective amount of imiquimod to the affected areaonce per day for fourteen (14) days or 2 weeks (cycle 2—treatment on)for a total of twenty-eight (28) doses or 4 weeks of application therapyto effectively treat actinic keratosis; or

(b) applying an effective amount of imiquimod to a treatment areaaffected with actinic keratosis once per day for twenty-one (21)consecutive days or 3 weeks (cycle 1-treatment on), followed by noapplication for twenty-one (21) days or 3 weeks (treatment off),followed by again applying an effective amount of imiquimod once per dayto the affected area for twenty-one (21) days or 3 weeks (cycle2—treatment on) for a total of forty-two (42) doses or 6 weeks ofapplication therapy to effectively treat actinic keratosis.

As indicated above, when the short durations of therapy are used incombination with the lower dosage strength imiquimod formulations of thepresent invention, it is surprisingly found that (1) simplified dailydosing regimens can be used, (2) the treatment area can be expanded,e.g., to treat greater than about 25 cm², e.g., areas as large asapproximately 200 cm²-250 cm² or more (e.g., full face or balding scalp)may now be treated, and (3) the number of AK lesions to be treated ishigher, e.g., to between about 5 and about 20 AK lesions or more pertreatment area. Also quite surprisingly, it is found that the expandedtreatment area and increased number of AK lesions can be effectivelytreated with lower dosage strength imiquimod formulations withoutinducing significant local skin reactions or irritation in the treatmentarea or treatment limiting adverse events which could result inpremature therapy termination or significant voluntary rest periods ofseveral days that are generally associated with higher concentrations ofimiquimod therapy. It is also surprisingly found that as much as betweenabout 250 mg and 500 mg or more of a low dosage strength imiquimodformulation may be used per application in accordance with the presentinvention, especially when the short durations of therapy are used incombination with the low dosage strength imiquimod formulations of thepresent invention.

In comparison, the Aldara® 5% imiquimod cream approved by the FDA foractinic keratosis concerns a treatment area defined as one contiguousarea of approximately 25 cm² on the face (e.g., forehead or one cheek)or the scalp, treating no more than about 4 to about 8 AK lesions pertreatment area, a dosing schedule of only twice per week for a full 16weeks to the defined treatment area on the face or scalp (but not bothconcurrently) and the application of no more than 250 mg of Aldara® 5%imiquimod cream formulation to the treatment area per application.

Also quite surprisingly, local skin reaction sum scores and mean localskin reaction erythema scores that are generated during the shortdurations of therapy with lower dosage strength imiquimod formulationsin accordance with the present invention create unique bimodal orcamelback patterns which parallel the 2-cycle imiquimod treatments ofthe present invention, wherein (1) the highest local skin reaction sumscore and the mean local skin reaction erythema score generally andcharacteristically occur or peak during or at the end of the first cycleof treatment, (2) the local skin reaction sum score and the mean localskin reaction erythema score return to normal or baseline or aboutnormal or baseline at the end of the no treatment period between cycles,(3) the local skin reaction sum score and the mean local skin reactionerythema score are again experienced by the subject during or at the endof the second cycle of treatment at generally but not necessarily areduced score, as compared to the local skin reaction sum score and themean local skin reaction erythema score during the first cycle oftreatment, and (4) the local skin reaction sum score and the mean localskin reaction erythema score generally return to normal or base lineshortly after the second cycle of treatment. See, e.g., FIGS. 18, 18A-B,20, 20A-B and 43-50 and Example 28. When the bimodal or camelbackpattern of local skin reaction sum score and mean local skin reactionerythema score are plotted as 2-dimensional graphs, wherein the localskin reaction sum score and the mean local skin reaction erythema scoreare measured on the vertical axis and the subject visits during theimiquimod 2-cycle therapy are measured on the horizontal axis, theunique bimodal or camelback patterns are observed. See, e.g., FIGS. 18,18A-B, 20, and 20A-B. Given this unexpected result that the local skinreaction sum score and the mean local skin reaction erythema score aregenerally decreasing overall during the course of therapy and return toabout normal or baseline at the end of the two-week no treatment periodbetween the two treatment cycles and again return to normal or baselineat about the end of the second cycle of treatment, imiquimod therapycompliance should be significantly improved and the therapeutic results,e.g., complete clearance or partial clearance or reduction of AKlesions, more consistently achieved.

Also quite surprisingly, the efficacy achieved by the lower dosagestrength imiquimod formulations when used in either of the shortdurations of therapy, e.g., two-week or three-week 2-cycle treatmentregimens, of the present invention for treatment of actinic keratosis asto total clearance, partial clearance and a reduction in the number ofAK lesions is statistically significant over placebo. See, e.g., FIG.51. It is also surprising that the efficacy achieved for treatment ofactinic keratosis as to complete clearance or partial clearance of AKlesions is basically statistically equivalent between the lower dosagestrength imiquimod formulations two-week or three-week 2-cycle treatmentregimens of the present invention when the same lower dosage strengthimiquimod formulations are used in accordance with either 2-cycletreatment regimen and compared with one another between the two 2-cycletreatment regimens. See, e.g., FIG. 51. Even more surprising, however,the efficacy achieved by a lower dosage strength 3.75% imiquimodformulation when used in either a two-week or three-week 2-cycletreatment regimen of the present invention for treatment of actinickeratosis as for partial clearance of AK lesions is statisticallysignificant over a lower dosage strength 2.5% imiquimod formulation whenused in either a two-week or three-week 2-cycle treatment regimen. See,e.g., FIG. 51. Nevertheless, it should be noted that the efficacies thatare achieved for complete clearance and partial clearance for eitherlower dosage strength imiquimod formulation, i.e., 2.5% or 3.75%, whenthey are used in either a two-week or three-week 2-cycle treatmentregimen in accordance with the present invention are at about a 95%confidence level and a P value of less than about 0.001 versus placebo.See FIG. 51. It should also be noted that the efficacy P value that isachieved for partial clearance for a 3.75% lower dosage strengthimiquimod formulation versus a 2.5% lower dosage strength imiquimodformulation that is utilized in accordance with a two-week or three-week2-cycle treatment regimen of the present invention is about 0.047 orabout 0.034, respectively. See, e.g., FIG. 51.

It is also quite surprising that the efficacy achieved by a lower dosagestrength 3.75% imiquimod formulation when used in a two-week 2-cycletreatment regimen of the present invention for treatment of actinickeratosis as to a reduction in the number of AK lesions is statisticallysignificant over a lower dosage strength 2.5% imiquimod formulation whenused in a two-week 2-cycle treatment regimen, but no difference oressentially equivalent when both lower dosage strength imiquimodformulations are used in a three-week 2-cycle treatment regimen, inaccordance with the present invention. See, e.g., FIG. 51. It should benoted that the efficacy P value that is achieved for a percent reductionin the number of AK lesions for a 3.75% lower dosage strength imiquimodformulation versus a 2.5% lower dosage strength imiquimod formulationthat is utilized in accordance with a two-week or three-week 2-cycletreatment regimen of the present invention is about 0.048 or about0.133, respectively. However, the 0.133 P value is not statisticallysignificant. See, e.g., FIG. 51.

It is also quite surprisingly found that it is believed that nostatistical significance in efficacy is achieved between a three-week2-cycle treatment regimen versus a two-week 2-cycle treatment regimenregardless of the lower dosage strength imiquimod formulation used totreat actinic keratosis. See, e.g., FIG. 52. In other words, there isbelieved to be no additional efficacy benefit with the longer 3 week2-cycle treatment regimen than the two week 2-cycle treatment regimen ofthe present invention to treat actinic keratosis, irrespective of whichlower dosage strength imiquimod formulation is used in either of the2-cycle treatment regimens in accordance with the present invention.See, e.g., FIGS. 52, 1-13G, 25-27, 36-38A and 42. It should be notedthat the P values that are achieved for (a) complete clearance, (b)partial clearance and (c) a reduction in the number of lesions, for thetwo-week 2-cycle treatment regimens and the three-week 2-cycle treatmentregimens of the present invention are (a) about 0.462 General LinearModel (“GLM”) and about 0.499 (LA), (b) about 0.233 (GLM) and about0.164 (LA), and (c) about 0.635 (GLM), respectively. See, e.g., FIG. 52.

While it is believed that there is no greater efficacy achieved betweenthe two 2-cycle treatment regimens of the present invention, it is foundthat there is generally a greater incidence of side effects, e.g., localskin reactions, and rest periods associated with the three-week 2-cycletreatment period as compared with the two-week 2-cycle treatment periodwhen the same lower dosage strength imiquimod formulation is used ineach of the 2-cycle treatment regimens in accordance with the presentinvention. Even though there is an increase in incidence of side effectsand rest periods associated with the three week 2-cycle treatmentregimen, it is believed that an acceptable safety profile is stillmaintained when using either the two-week or three-week 2-cycletreatment regimens in accordance with the present invention. See, e.g.,FIGS. 14A-23, 28, 28A-B and 39-42. Nonetheless, it is quite surprisinglyfound that there is a lower subject incidence of application sitereactions associated with either of the 2-cycle treatment periods of thepresent invention than associated with use of the Aldara® 5% imiquimodcream to treat actinic keratosis in accordance with the FDA-approvedtreatment regimen, even though the Aldara® 5% imiquimod cream is appliedonly twice weekly to a treatment area of approximately 25 cm² for 16weeks. See, e.g., FIGS. 28, 28A-B, 41 and 41A. Thus, it should beunderstood by those versed in this art that, while both 2-cycletreatment regimens of the present invention provide efficacious dosingregimens with acceptable safety profiles, that are short and moreconvenient for patient use than the dosing regimen currently approved bythe FDA for Aldara® 5% imiquimod cream, to treat actinic keratosis, the2 week 2-cycle treatment regimen of the present invention is preferred.It should also be understood that the short durations of therapy andlower dosage strength imiquimod formulations of the present inventionare believed to be optimized to treat actinic keratosis. By “optimized”,it is meant herein that the short durations of therapy and lower dosagestrength imiquimod formulations of the present invention are designed toachieve efficacy, stability and release rates profiles that are at leastessentially equivalent to and linear with Aldara® 5% imiquimod cream,respectively, but with an improved acceptable safety profile.

By the term “acceptable safety profile”, it is meant herein to mean thattreatment of actinic keratosis with a short duration of therapy and alower dosage strength imiquimod formulation in accordance with thepresent invention, including the 2-cycle treatment regimens, does notcause treatment limiting side effects or rest periods in an appreciablenumber of subjects undergoing actinic keratosis therapy to a level thatcauses premature termination of treatment. The term “acceptable safetyprofile” also refers to treatment of actinic keratosis with a shortduration of therapy and a lower dosage strength imiquimod formulation ofthe present invention with a lower subject incidence of application sitereactions as compared with treatment of actinic keratosis with Aldara®5% imiquimod cream.

Also quite surprisingly, it is found that, when a lower dosage strengthimiquimod formulation, i.e., about 2.5%, is used in a 2-cycle, 2×2×2weeks, treatment regimen in accordance with the present invention, totreat actinic keratosis diagnosed in females, a clearance rate,inclusive of complete clearance and partial clearance, of about 60% isachieved. See FIG. 31. Equally surprising, it is found that when a lowdosage strength imiquimod formulation, i.e., about 3.75%, is used ineither a 2-cycle, 2×2×2 week or a 2-cycle, 3×3×3 weeks, treatmentregimen in accordance with the present invention, to treat actinickeratosis diagnosed in male or female subjects or in subjects with TypeI, II or III skin, about 10 lesions or less at baseline, or with lesionson the face or scalp, equivalent or comparable clearance rates,inclusive of complete clearance and partial clearance, are achieved.See, e.g., FIGS. 31, 33, 33A, 34, 34A, 35 and 35A-B. Also surprising, itis found that when a low dosage strength imiquimod formulation, i.e.,about 3.75%, is used in either a 2-cycle, 2×2×2 week or a 2-cycle, 3×3×3week, treatment regimen in accordance with the present invention, totreat actinic keratosis diagnosed in subjects who are 65 years of age orolder or in subjects who have greater than 10 lesions at baseline, the2-cycle, 2×2×2 week treatment regimen is more effective. See, e.g.,FIGS. 32, 32A, 34 and 34A.

It is also surprisingly found that, when a lower dosage strengthimiquimod formulation is used in connection with a short duration oftherapy, e.g., either a two-week or three-week 2-cycle treatmentregimen, of the present invention for treatment of actinic keratosis,the Investigators Global Integrated Photodamage (“IGIP”) score issignificantly or much improved as compared with baseline. See, e.g.,FIGS. 24 and 53. For example, and as shown in FIG. 53, when the 3.75%imiquimod studies are combined, approximately 44% (132 of 299) of thesubjects under going treatment show significant improvement,approximately 25% (76 of 299) of the subjects under going treatment showmuch improvement and approximately 17% (51 of 299) of the subjects undergoing treatment show slight improvement in the IGIP score from baseline,whereas when the 2.5% imiquimod studies are combined, approximately 32%(97 of 304) of the subjects under going treatment show significantimprovement, approximately 26% (78 of 304) of the subjects under goingtreatment show much improvement and approximately 23% (69 of 304) of thesubjects under going treatment show slight improvement in the IGIP scorefrom baseline.

The salient elements of a pharmaceutical formulation according to thepresent invention are (a) imiquimod and (b) a fatty acid, e.g.,isostearic, palmitic, stearic, linoleic, unrefined oleic acid or refinedoleic acid, such as Super Refined® oleic acid NF (e.g., a highlypurified oleic acid, i.e., an oleic acid which has low polar impurities,such as peroxides, a low peroxide value and is marketed by CRODA; seee.g., www.crodausa.com) and mixtures thereof. A pharmaceuticalformulation of the invention can be in any form known to the art, suchas a cream, an ointment, a foam, a gel, a lotion or a pressure-sensitiveadhesive composition, each form containing the necessary elements inparticular amounts and further containing various additional elements.

A cream of the invention contains an effective amount of imiquimod, suchas between about greater than 1 percent and about 4.25 percent by weightof imiquimod, based on the total weight of the cream; about 5 percent toabout 30 percent by weight of fatty acid, based on the total weight ofthe cream; and optional ingredients such as emollients, emulsifiers,thickeners, and/or preservatives.

An ointment of the invention contains an ointment base in addition toimiquimod and fatty acid. An ointment of the invention contains aneffective amount of imiquimod, such as between about greater than 1percent and about 4.25 percent by weight of imiquimod; about 3 percentto about 45 percent, more preferably about 3 percent to about 30 percentby weight fatty acid; and about 40 percent to about 95 percent by weightointment base, all weights being based on the total weight of theointment. Optionally, an ointment of the invention can also containemulsifiers, emollients and thickeners.

A pressure-sensitive adhesive composition of the invention containsimiquimod, fatty acid, and an adhesive. The adhesives utilized in apressure sensitive adhesive composition of the invention are preferablysubstantially chemically inert to imiquimod. A pressure sensitiveadhesive composition of the invention preferably contains an effectiveamount of imiquimod, such as between about greater than 1 percent andabout 4.25 percent by weight of imiquimod; about 10 percent to about 40percent by weight, more preferably of about 15 percent to about 30percent by weight, and most preferably about 20 percent to about 30percent by weight of fatty acid; all weights being based on the totalweight of the pressure sensitive adhesive composition.

Optionally, pressure sensitive adhesive compositions of the inventioncan also contain one or more skin penetration enhancers. The totalamount of skin penetration enhancer(s) present in a pressure sensitiveadhesive composition of the invention is preferably about 3 percent toabout 25 percent by weight, and more preferably about 3 percent to about10 percent by weight based on the total weight of the pressure sensitiveadhesive composition.

A pressure-sensitive adhesive coated sheet material of the invention canbe made from a pressure-sensitive adhesive composition of the inventionin the form of an article such as a tape, a patch, a sheet, or adressing.

A lower dosage strength formulation of the present invention may be usedto topically and/or transdermally administer an effective amount ofimiquimod to effectively treat actinic keratosis with short durations oftherapy and with an acceptable safety profile. Thus, lower dosagestrength formulations according to the present invention can be appliedto any suitable location, for example, topically to dermal, lip and/ormucosal surfaces. In the case of dermal application, for example,depending on the concentration, formulation composition, and dermalsurface, the therapeutic effect of imiquimod may extend only to thesuperficial layers of the dermal surface or to tissues below the dermalsurface.

It should be understood that while lower dosage strength formulations ofthe present invention containing, by weight based on the total weight ofthe formulation, between about 1% and about 4.25% imiquimod arecontemplated, preferably between about 1.5%, 1.75%, 2.0%, 2.25%, 2.5%,2.75%, 3.0%, 3.25%, 3.5%, 3.75%, 4.0% and 4.25%, and even morepreferably between about 2.0%, 2.25%, 2.5%, 2.75%, 3.0%, 3.25%, 3.5%,3.75% and 4.0%, and still even more preferably between about 2.5%,2.75%, 3.0%, 3.25%, 3.5% and 3.75% are contemplated. Lower dosagestrength formulations of the present invention that contain about 2.5%imiquimod or about 3.75% imiquimod by weight based on the total weightof the formulation are most preferred. It should also be understood thatlower dosage strength imiquimod formulations of the present invention,which have dose proportionate release rates as to both the release ratesof the imiquimod and the total amount of imiquimod released, relative tothe Aldara® 5% imiquimod cream, are also preferred.

Thus, it should be understood by those versed in this art that an amountof imiquimod present in a formulation of the present invention will bean effective amount when a formulation of the present invention isapplied daily in accordance with a short duration of therapy asdescribed herein to a targeted area diagnosed with actinic keratosis andpermitted following each individual application to remain in contactwith the targeted area for a sufficient time to allow an effectiveamount of imiquimod to clear such a disease or lesions of the disease,to partially clear the number of lesions of such a disease, to reducethe number of lesions, to prevent the recurrence of such a diseasewithout inducing treatment limiting local skin reactions or adverseevents, including unscheduled rest periods caused by such treatmentlimiting local skin reactions or adverse events, in an appreciablenumber of people undergoing treatment. For example, when treatingactinic keratosis in accordance with the present invention, an effectiveamount will achieve a partial clearance in AK lesions as a targetedendpoint, e.g., at least about 40% and preferably at least about 50% andmore preferably at least about 60% and still more preferably at leastabout 70% and most preferably at least about a 75% reduction in thenumber of AK lesions in the treatment area compared with baseline, or atleast about 60% and preferably at least about 70% and even morepreferably at least about 80% and most preferably at least about 90%median reduction in the number of AK lesions in the treatment areacompared with baseline as a secondary endpoint, or at least about 25%complete clearance and preferably at least about 30% complete clearanceand even more preferably at least about 35% complete clearance and mostpreferably at least about 45% complete clearance of the AK lesions as aprimary endpoint. See, e.g., FIGS. 36, 36A, 37, 37A, 38, 38A, 51 and 52.By “complete clearance”, as used herein, the term means the absence ofclinically visible or palpable AK lesions in the treatment area.

Results from use of the lower dosage strength imiquimod formulations inaccordance with the short durations of therapy of the present inventiondemonstrate that lower dosage strength imiquimod formulations dosed oncedaily for two week or three week 2 cycle treatment periods are effectiveand well-tolerated treatments for actinic keratosis on the face orbalding scalp. The condensed dosing regimens of the present inventionallows for short treatment periods, minimizing exposure to imiquimod andfurther supporting an improved benefit-risk profile, as compared withFDA-approved Aldara® 5% imiquimod cream 16 week, twice-weekly therapy.

Benefits of treatment with the lower dosage strength imiquimodformulations in accordance with the short durations of therapy of thepresent invention include complete clearance or partial clearance (≧66%,preferably ≧75%, even more preferably ≧88% and even more preferably≧95%) of AK lesions for a majority of the subjects that are treated. SeeExample 24 and FIGS. 51 and 52. More particularly, complete or partialclearances of AK lesions are achieved as follows: (1) ≧35% (57 of 160subjects) complete clearance is achieved for a 2-week 2 cycle treatmentusing a 3.75% lower dosage strength imiquimod formulation of the presentinvention; (2) ≧30% (49 of 160 subjects) complete clearance is achievedfor a 2-week 2 cycle treatment using a 2.5% lower dosage strengthimiquimod formulation of the present invention; (3) ≧34% (55 of 162subjects) complete clearance is achieved for a 3-week 2 cycle treatmentusing a 3.75% lower dosage strength imiquimod formulation of the presentinvention; and (4) ≧25% (41 of 164 subjects) complete clearance isachieved for a 2-week 2 cycle treatment using a 2.5% lower dosagestrength imiquimod formulation of the present invention; whereas (5)≧59% (95 of 160 subjects) partial clearance is achieved for a 2-week 2cycle treatment using a 3.75% lower dosage strength imiquimodformulation of the present invention; (6) ≧48% (77 of 160 subjects)partial clearance is achieved for a 2-week 2 cycle treatment using a2.5% lower dosage strength imiquimod formulation of the presentinvention; (7) ≧53% (87 of 162 subjects) partial clearance is achievedfor a 3-week 2 cycle treatment using a 3.75% lower dosage strengthimiquimod formulation of the present invention; and (8) ≧42% (70 of 164subjects) partial clearance is achieved for a 2-week 2 cycle treatmentusing a 2.5% lower dosage strength imiquimod formulation of the presentinvention. Although subjects who are treated with the lower dosagestrength imiquimod formulations in accordance with the short durationsof therapy of the present invention may experience local skin reactions(LSRs), see, e.g., FIGS. 16A-20, 20A-B and 29 and 40, the treatment iswell tolerated and there is a marked lower subject incidence ofapplication site reactions, e.g., see FIGS. 14A-E, 28, 28A-B, 41 and41A, as compared with the longer FDA-approved Aldara® 5% imiquimod creamtreatment regimen, i.e., 16 weeks, twice weekly, for AK therapy.

This same larger “treatment area” of the present invention may bedefined as an area of greater than 25 cm² (e.g., a treatment areagreater than a 5 cm×5 cm area in any shape) and up to between about 200cm² and 250 cm² or more on the face (e.g. forehead or one cheek) or onthe balding scalp, including the full face or entire balding scalp. Thenumber of AK lesions to be treated in the treatment area may range fromabout 5 to about 20 or more. It should be also appreciated by thoseversed in this art that the present invention also affords the addedbenefit of the uncovering and clinical appearance and subsequentcomplete or partial eradication of incipient (subclinical) AK lesions inthe treatment area. It is presently believed that, because the treatmentarea exceeds 25 cm², the lower dose strength imiquimod formulations andthe short durations of therapy, when practiced in accordance with thepresent invention, will increase subject tolerance and compliance,improve the therapeutic results, e.g., complete clearance or partialclearance or reduction of AK lesions, lower subject incidence ofapplication site reactions (see, e.g., FIGS. 28, 28A-B, 41 and 41A), andreduce voluntary rest periods (see, e.g., FIGS. 39 and 39A) duringtherapy, as compared to Aldara® 5% imiquimod cream if applied to thesame larger treatment area in accordance with the present invention.Moreover, it is believed that, because the expanded treatment area is somuch larger than the smaller treatment area, i.e., less than or equal toapproximately 25 cm², currently treated with Aldara® 5% imiquimod cream,the expanded treatment area of the present invention will be much moreweighted to non-lesional/normal skin than previously experienced withthe smaller treatment area treated with Aldara® 5% imiquimod cream.Preferably, the concentration of imiquimod applied is between about 1percent to about 4.25 percent by weight based on the total weight of aformulation of the present invention. Also, to treat actinic keratosisin accordance with the present invention, an effective amount ofimiquimod should be applied once per day for at least up to about 6weeks, e.g., once per day for a full 2 or 3 weeks (14 or 21 days) to adiagnosed or defined treatment area on, for example, the face or baldingscalp (cycle 1), then stopped or discontinued for 2 or 3 weeks (14 or 21days), a scheduled rest period, followed by application again once perday for a full 2 or 3 weeks (14 or 21 days) to the defined treatmentarea (cycle 2) to achieve a secondary and more preferably a primaryendpoint, e.g., to achieve at least about a 75% reduction in AK lesionsas a targeted secondary endpoint and more preferably complete clearanceof the AK lesions as a primary endpoint. Also when treating actinickeratosis in accordance with the two-week or three week 2-cycletreatment periods of the present invention, an effective amount ofimiquimod applied to the treatment area will not only achieve asecondary or primary endpoint, but will also induce a lower subjectincidence of application site skin reactions and a fewer number ofvoluntary rest periods taken by the subjects under going treatment,e.g., no more than about 11% and more preferably no more than about 7%of the subjects will take one or more rest periods during the shorttwo-week 2-cycle treatment period or no more than about 17% and morepreferably no more than about 27% of subjects will take one or more restperiods during the short three-week 2-cycle treatment period. See, e.g.,FIGS. 21, 39 and 39A.

While the present invention has identified what it believes to bepreferred concentrations of imiquimod formulations, numbers ofapplications per week and durations of therapy, it should be understoodby those versed in this art that any effective concentration ofimiquimod in a formulation that delivers an effective amount ofimiquimod and any numbers of application per week during a shortduration of therapy, as described herein, that can effectively treatactinic keratosis, without causing treatment limiting local skinreactions or related adverse events, including too many rest periods, iscontemplated by the present invention.

The above summary of the present invention is not intended to describeeach disclosed embodiment or every implementation of the presentinvention. The description that follows more particularly exemplifiesillustrative embodiments. In several places throughout the application,guidance is provided through lists of examples, which examples can beused in various combinations. In each instance, the recited list servesonly as a representative group and should not be interpreted as anexclusive list.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects, advantages and features of the presentinvention, and the manner in which the same are accomplished, willbecome more readily apparent upon consideration of the followingdetailed description of the invention taken in conjunction with theaccompanying figure and examples, which illustrate an embodiment,wherein:

FIG. 1 shows efficacy measures of complete clearance rates by study forstudies GW01-0702, GW01-0703, GW01-0704 and GW01-0705 for the 2-cycle2×2×2 (2 weeks) treatment regimen and for the 2-cycle 3×3×3 (3 weeks)treatment regimen;

FIG. 1A is a summary of primary and secondary efficacy endpoints for atwo-week treatment cycle regimen concerning ITT population for studiesGW01-0702 and GW01-0704. Complete clearance is defined as the absence ofclinically visible or palpable AK lesions in the treatment area. Partialclearance is defined as at least a 75% reduction in the number of AKlesions in the treatment area compared with Baseline. P values are fromCochran-Mantel-Haenszel test, stratified by analysis site, taking 2treatment groups at a time. The P values marked with ** arestatistically significant using Hochberg's modified Bonferroniprocedure. LOCF=Last observation that is carried forward. Confidenceintervals are calculated using exact binomial statistics. As used inthis FIG. 1A, “2.5%” refers to a 2.5% imiquimod lower dosage strengthformulation of Examples 23-28 and “3.75%” refers to a 3.75% imiquimodlower dosage strength formulation of Examples 23-28;

FIG. 2 shows efficacy measures of complete clearance, by time point, forstudies GW01-0702 and GW01-0704 for the 2-cycle 2×2×2 (2 weeks)treatment regimen. As used in this FIG. 2, “Complete Clearance” refersto the rate of complete clearance of AK lesions, “Cyc 2 Start” refers tothe start of the second cycle, “4 Weeks Post” refers to 4 weeks posttreatment, and “EOS” refers to End of Study;

FIG. 2A shows a rate of complete clearance vs. study week an ITTpopulation for study GW01-0702. Points that are marked with ** showsstatistically difference from placebo. As used in this FIG. 2A, “Rate ofComplete Clearance” refers to rate of complete AK lesion clearance, “A”refers to a 2.5% imiquimod lower dosage strength formulation of Examples23-28, “B” refers to a 3.75% imiquimod lower dosage strength formulationof Examples 23-28, and “C” refers to placebo;

FIG. 2B shows a rate of complete clearance vs. study week of an ITTpopulation for study GW01-0704. Points that are marked with ** showsstatistically difference from placebo. Points marked with ## showstatistically significant difference between active treatments. As usedin this FIG. 2B, “Rate of Complete Clearance” refers to rate of completeAK lesion clearance, “A” refers to a 2.5% imiquimod lower dosagestrength formulation of Examples 23-28, “B” refers to a 3.75% imiquimodlower dosage strength formulation of Examples 23-28, and “C” refers toplacebo;

FIG. 3 shows efficacy measures of complete clearance, by time point, forstudies GW01-0703 and GW01-0705 for the 2-cycle 3×3×3 (3 weeks)treatment regimen. As used in this FIG. 3, “Complete Clearance” refersto complete clearance of AK lesions, “Cyc 2 Start” refers to the startof the second cycle, “4 Weeks Post” refers to 4 weeks post treatment,and “EOS” refers to End of Study. See also FIGS. 2A and 2B;

FIG. 3A shows a rate of complete clearance vs. study week of an ITTpopulation for study GW01-0703. Points that are marked with ** showsstatistically difference from placebo. Points marked with ## showstatistically significant difference between active treatments. As usedin this FIG. 3A, “Rate of Complete Clearance” refers to rate of completeAK lesion clearance, “A” refers to a 2.5% imiquimod lower dosagestrength formulation of Examples 23-28, “B” refers to a 3.75% imiquimodlower dosage strength formulation of Examples 23-28, and “C” refers toplacebo;

FIG. 3B shows a rate of complete clearance vs. study week of an ITTpopulation for study GW01-0705. Points that are marked with ** showsstatistically difference from placebo. Points marked with ## showstatistically significant difference between active treatments. As usedin this FIG. 3B, “Rate of Complete Clearance” refers to rate of completeAK lesion clearance, “A” refers to a 2.5% imiquimod lower dosagestrength formulation of Examples 23-28, “B” refers to a 3.75% imiquimodlower dosage strength formulation of Examples 23-28, and “C” refers toplacebo;

FIG. 4A shows rates of partial clearance at end of study of a two-weektreatment cycle regimen of an ITT population for studies GW01-0702 andGW01-0704. In this FIG. 4A, “Rate of Partial Clearance” refers to rateof partial AK lesion clearance (defined as at least about 75% reductionin the number of AK lesions in the treatment area as compared withBaseline), “L” refers to a 2.5% imiquimod lower dosage strengthformulation of Examples 23-28, “H” refers to a 3.75% imiquimod lowerdosage strength formulation of Examples 23-28, P=placebo, and that thebars marked with ** show statistically significant difference fromplacebo, whereas the bars marked with ## show statistically significantdifference from 2.5%. The vertical blue lines indicate 95% confidencelimits;

FIG. 4B shows a rate of partial clearance at week 14 for an ITTpopulation for study GW01-0702. Partial clearance is defined as at leasta 75% reduction in the number of AK lesions in the treatment areacompared with baseline. The bars marked with ** show statisticallysignificant difference from placebo. Dark black vertical lines represent95% confidence intervals on the rates. In this FIG. 4B, “Rate of PartialClearance” refers to rate of partial AK lesion clearance (defined as atleast about 75% reduction in the number of AK lesions in the treatmentarea as compared with Baseline), “2.5%” refers to a 2.5% imiquimod lowerdosage strength formulation of Examples 23-28, and “3.75%” refers to a3.75% imiquimod lower dosage strength formulation of Examples 23-28;

FIG. 4C shows a rate of partial clearance at week 14 for an ITTpopulation for study GW01-0704. Partial clearance is defined as at leasta 75% reduction in the number of AK lesions in the treatment areacompared with baseline. The bars marked with ** show statisticallysignificant difference from placebo. The bars marked with ## showstatistically difference between active treatments. Dark black verticallines represent 95% confidence intervals on the rates. In this FIG. 4C,“Rate of Partial Clearance” refers to rate of partial AK lesionclearance (defined as at least about 75% reduction in the number of AKlesions in the treatment area as compared with Baseline), “2.5%” refersto a 2.5% imiquimod lower dosage strength formulation of Examples 23-28,and “3.75%” refers to a 3.75% imiquimod lower dosage strengthformulation of Examples 23-28;

FIG. 4D shows a rate of partial clearance at week 17 for an ITTpopulation for study GW01-0703. Partial clearance is defined as at leasta 75% reduction in the number of AK lesions in the treatment areacompared with baseline. The bars marked with ** show statisticallysignificant difference from placebo. Dark black vertical lines represent95% confidence intervals on the rates. In this FIG. 4D, “Rate of PartialClearance” refers to rate of partial AK lesion clearance (defined as atleast about 75% reduction in the number of AK lesions in the treatmentarea as compared with Baseline), “2.5%” refers to a 2.5% imiquimod lowerdosage strength formulation of Examples 23-28, and “3.75%” refers to a3.75% imiquimod lower dosage strength formulation of Examples 23-28;

FIG. 4E shows a rate of partial clearance at week 17 for an ITTpopulation for study GW01-0705. Partial clearance is defined as at leasta 75% reduction in the number of AK lesions in the treatment areacompared with baseline. The bars marked with ** show statisticallysignificant difference from placebo. Dark black vertical lines represent95% confidence intervals on the rates. In this FIG. 4E, “Rate of PartialClearance” refers to rate of partial AK lesion clearance (defined as atleast about 75% reduction in the number of AK lesions in the treatmentarea as compared with Baseline), “2.5%” refers to a 2.5% imiquimod lowerdosage strength formulation of Examples 23-28, and “3.75%” refers to a3.75% imiquimod lower dosage strength formulation of Examples 23-28;

FIG. 4F shows a rate of partial clearance vs. study time point combinedstudies for an ITT population regarding the use of a 3.75% lower dosagestrength imiquimod formulation of Examples 23-28. Note the followingL2=2.5% two-week treatment cycle regimen, L3=2.5% three-week treatmentcycle regimen, H2=3.75% two-week treatment cycle regimen, H3=3.75%three-week treatment cycle regimen, P2=placebo two-week treatment cycleregimen, and P3=placebo three-week treatment cycle regimen. In this FIG.4F, “Rate of Partial Clearance” refers to rate of partial AK lesionclearance (defined as at least about 75% reduction in the number of AKlesions in the treatment area as compared with Baseline), “Start ofCycle 2” refers to the start of the second cycle, “4 Weeks Post” refersto 4 weeks post treatment, and “8 Weeks Post” refers to 8 weeks posttreatment;

FIG. 5 shows efficacy measures of partial clearance, by time point, forstudies GW01-0702 and GW01-0704. See also FIG. 37A. As used in this FIG.5, “Partial Clearance” refers to partial clearance of AK lesions(defined as at least about 75% reduction in the number of AK lesions inthe treatment area as compared with Baseline), “Cyc 2 Start” refers tothe start of the second cycle, “4 Weeks Post” refers to 4 weeks posttreatment, “EOS” refers to End of Study, and “2×2×2” refers to a twoweek, 2-cycle treatment, as through out the FIGS. and the specification;

FIG. 5A shows a rate of partial clearance vs. study week for an ITTpopulation for study GW01-0702. The points marked with ** showsstatistically difference from placebo. The points marked with ## showsstatistically difference between active treatments. As used in this FIG.5A, “Rate of Partial Clearance” refers to rate of partial AK lesionclearance (defined as at least about 75% reduction in the number of AKlesions in the treatment area as compared with Baseline), “A” refers toa 2.5% imiquimod lower dosage strength formulation of Examples 23-28,“B” refers to a 3.75% imiquimod lower dosage strength formulation ofExamples 23-28, and “C” refers to placebo;

FIG. 5B shows a rate of partial clearance vs. study week for an ITTpopulation for study GW01-0704. The points marked with ** showsstatistically difference from placebo. The points marked with ## showsstatistically difference between active treatments. As used in this FIG.5B, “Rate of Partial Clearance” refers to rate of AK partial lesionclearance (defined as at least about 75% reduction in the number of AKlesions in the treatment area as compared with Baseline), “A” refers toa 2.5% imiquimod lower dosage strength formulation of Examples 23-28,“B” refers to a 3.75% imiquimod lower dosage strength formulation ofExamples 23-28, and “C” refers to placebo;

FIG. 6 shows efficacy measures of partial clearance, by time point, forstudies GW01-0703 and GW01-0705. As used in this FIG. 6, PartialClearance” refers to rate percent of partial clearance of AK lesions(defined as at least about 75% reduction in the number of AK lesions inthe treatment area as compared with Baseline), “Cyc 2 Start” refers tothe start of the second cycle, “4 Weeks Post” refers to 4 weeks posttreatment, and “EOS” refers to End of Study. See also FIG. 37A;

FIG. 6A shows a rate of partial clearance vs. study week for an ITTpopulation for study GW01-0703. The points marked with ** showsstatistically significant difference from placebo. The points markedwith ## shows statistically significant difference between activetreatments. As used in this FIG. 6A, “Rate of Partial Clearance” refersto rate of partial AK lesion clearance (defined as at least about 75%reduction in the number of AK lesions in the treatment area as comparedwith Baseline), “A” refers to a 2.5% imiquimod lower dosage strengthformulation of Examples 23-28, “B %” refers to a 3.75% imiquimod lowerdosage strength formulation of Examples 23-28, and “C” refers toplacebo;

FIG. 6B shows a rate of partial clearance vs. study week for an ITTpopulation for study GW01-0705. The points marked with ** showsstatistically significant difference from placebo. The points markedwith ## shows statistically significant difference between activetreatments. As used in this FIG. 6B, “Rate of Partial Clearance” refersto rate of partial AK lesion clearance (defined as at least about 75%reduction in the number of AK lesions in the treatment area as comparedwith Baseline), “A” refers to a 2.5% imiquimod lower dosage strengthformulation of Examples 23-28, “B” refers to a 3.75% imiquimod lowerdosage strength formulation of Examples 23-28, and “C” refers toplacebo;

FIG. 7 shows efficacy measures of mean % change from baseline count, bystudy, for studies GW01-0703, GW01-0702, GW01-0704 and GW01-0705. Seealso FIG. 9A;

FIG. 8 shows efficacy measures of mean % change from baseline count, bytime point, for studies GW01-0702 and GW01-0704. As used in this FIG.8,“% Count Reduction” refers to the percent reduction in AK count fromBaseline, “Cyc 2 Start” refers to the start of the second cycle, “4Weeks Post” refers to 4 weeks post treatment, and “EOS” refers to End ofStudy. See also FIG. 9A;

FIG. 8A shows a median percent change from baseline AK lesion count vs.study week for an ITT population for study GW01-0702. The points markedwith ** shows statistically significant difference from placebo. Thepoints marked with ## shows statistically significant difference betweenactive treatments. As used in this FIG. 8A, “Median Percent Change”refers to median percent change in AK lesion count from Baseline, “A”refers to a 2.5% imiquimod lower dosage strength formulation of Examples23-28, “B” refers to a 3.75% imiquimod lower dosage strength formulationof Examples 23-28, and “C” refers to placebo;

FIG. 8B shows a median percent change from baseline AK lesion count vs.study week for an ITT population for study GW01-0704. The points markedwith ** shows statistically significant difference from placebo. Thepoints marked with ## shows statistically significant difference betweenactive treatments. As used in this FIG. 8B, “Median Percent Change”refers to median percent change in AK lesion count from Baseline, “A”refers to a 2.5% imiquimod lower dosage strength formulation of Examples23-28, “B %” refers to a 3.75% imiquimod lower dosage strengthformulation of Examples 23-28, and “C” refers to placebo;

FIG. 9 shows efficacy measures of mean % change from baseline count, bytime point, for studies GW01-0703 and GW01-0705. As used in this FIG. 9,“Mean % Change from Baseline Count” refers to the mean percent reductionin AK count, “Cyc 2 Start” refers to the start of the second cycle, “4Weeks Post” refers to 4 weeks post treatment, and “EOS” refers to End ofStudy. See also FIGS. 8A and 8B;

FIG. 9A shows a summary of AK lesion Count for an ITT populationregarding GW01-0703. As used in this FIG. 9A, “2.5%” refers to a 2.5%imiquimod lower dosage strength formulation of Examples 23-28 and“3.75%” refers to a 3.75% imiquimod lower dosage strength formulation ofExamples 23-28. The P values are from the Cochran-Mantel-Haenszel test,that is stratified by analysis site, taking two treatment groups at atime. The P values marked with ** are statistically significant usingHochberg's modified Bonferroni procedure. Lesion counts which arerecorded as ‘indeterminate’ are excluded from analysis;

FIG. 9B shows a summary of AK lesion Count for an ITT populationregarding GW01-0705. As used in this FIG. 9A, “2.5%” refers to a 2.5%imiquimod lower dosage strength formulation of Examples 23-28 and“3.75%” refers to a 3.75% imiquimod lower dosage strength formulation ofExamples 23-28. The P values are from the Cochran-Mantel-Haenszel test,that is stratified by analysis site, taking two treatment groups at atime. The P values marked with ** are statistically significant usingHochberg's modified Bonferroni procedure. Lesion counts which arerecorded as ‘indeterminate’ are excluded from analysis;

FIG. 10 shows efficacy measures of clearance rates, by subject sex, forstudies GW01-0703, GW01-0702, GW01-0704 and GW01-0705. As used in thisFIG. 10, “Rate of Clearance” refers to the rate of complete AK lesionclearance;

FIG. 10A shows a summary of primary and secondary efficacy endpoints formale and female subpopulations for combined two-week treatment cyclestudies GW01-0702 and GW01-0704 for an ITT population using either a2.5% or a 3.75% lower dosage strength imiquimod formulation of Examples23-28. The P values for clearance rates are from a generalized linearmodule (GENMOD), assuming a multinomial distribution (DIST=MULT) and acumulative logit link function (LINK=CLOGIT), including effects of dose,subpopulation, and interaction. The P values for percent change in AKlesion count are from the analysis of variance (GLM) including effectsof dose, subpopulation, and interaction;

FIG. 10B shows a summary of primary efficacy variable, rate of completeclearance at week 17 (end of study) subgroup analysis n/N (%) for studyGW01-0703 using either a 2.5% or a 3.75% lower dosage strength imiquimodformulation of Examples 23-28;

FIG. 10C shows a summary of primary efficacy variable, rate of completeclearance at week 17 (end of study) subgroup analysis n/N (%) for studyGW01-0705 using either a 2.5% or a 3.75% lower dosage strength imiquimodformulation of Examples 23-28;

FIG. 11 shows efficacy measures of clearance rates, by subject treatmentarea, for studies GW01-0703, GW01-0702, GW01-0704 and GW01-0705. As usedin this FIG. 11, “Rate of Clearance” refers to the rate of complete AKlesion clearance;

FIG. 12 shows efficacy measures of median percent change from baselinebetween 0 and −100 for studies GW01-0703, GW01-0702, GW01-0704 andGW01-0705. As used in this FIG. 11, “Percent Change” refers to themedian percent by which there is a change in the number of AK lesionsusing either a 2.5% or a 3.75% lower dosage strength imiquimodformulation of Examples 23-28 in either a two, 2-cycle or a three week,2-cycle treatment;

FIG. 12A shows a median percent change from baseline in number of AKlesions vs. study timepoint for combined studies for an ITT populationusing either a 2.5% or a 3.75% lower dosage strength imiquimodformulation of Examples 23-28. Note the following: L2=2.5% two-weektreatment cycle regimen, L3=2.5% three-week treatment cycle regimen,H2=3.75% two-week treatment cycle regimen, H3=3.75% three-week treatmentcycle regimen, P2=placebo two-week treatment cycle regimen, andP3=placebo three-week treatment cycle regimen. As used in this FIG. 12A,“Median Percent Change” refers to the median percent change in number ofAK lesions from baseline, “Start of Cycle 2” refers to the start of thesecond cycle, “4 Weeks Post” refers to 4 weeks post treatment, “8 WeeksPost” refers to 8 weeks post treatment, and “P” refers to placebo;

FIG. 13 shows efficacy measures of mean percent change from baselinebetween 0 and −80 for studies GW01-0703, GW01-0702, GW01-0704 andGW01-0705 using either a 2.5% or a 3.75% lower dosage strength imiquimodformulation of Examples 23-28. As used in this FIG. 13, “Percent Change”refers to the mean percent change in number of AK lesions from baseline,“Cyc 2 Start” refers to the start of the second cycle, “4 Weeks Post”refers to 4 weeks post treatment, and “EOS” refers to End of Study (8weeks post treatment);

FIGS. 13A-G show a summary of percent change from baseline in number ofAK lesions by visit for combined studies for an ITT population usingeither a 2.5% or a 3.75% lower dosage strength imiquimod formulation ofExamples 23-28. The P values are from the Cochran-Mantel-Haenszel test,that is stratified by analysis site, taking two treatment groups at atime. The P values marked with ** are statistically significant usingHochberg's modified Bonferroni procedure;

FIGS. 14A-E show a summary of treatment-emergent adverse events n (%) ofsubjects in descending order of incidence in a 3.75% or 2.5% two-week orthree-week treatment cycle group where the adverse events are consideredtreatment related by the investigator for combined studies for an ITTpopulation using either a 2.5% or a 3.75% lower dosage strengthimiquimod formulation of Examples 23-28. The counts reflect number ofsubjects in each treatment group reporting one or more adverse eventsthat map to the MedDRA system organ class. A subject may be counted onlyonce in each row of the table. Treatment-related includes ProbablyRelated and Related. A treatment-emergent AE is an AE with onset date onor after day 1 of treatment;

FIG. 15 shows safety measures of incidence of treatment-related adverseevents for studies GW01-0703, GW01-0702, GW01-0704 and GW01-0705. Asused in this FIG. 15, “H” refers to a 3.75% lower dosage strengthimiquimod formulation of Examples 23-28 and “L” refers to a 2.5% lowerdosage strength imiquimod formulation of Examples 23-28, and “V” refersto vehicle. See also FIGS. 14A-14E;

FIGS. 16A-C show a summary of local skin reactions (LSR) for most severereaction grade during study overall for combined studies for an ITTpopulation using a 2.5% or a 3.75% lower dosage strength imiquimodformulation in 2 week or 3 week two-cycle therapies in accordance withthe present invention. Because a subject in the two-week 3.75% treatmentgroup, a subject in the three-week 2.5% treatment, a subject in the3.75% treatment group and two subjects in the three-week placebo groupdo not have post-baseline visits, they are excluded from the analysis;

FIG. 17 shows safety measures of LSR AUC sum score for studiesGW01-0703, GW01-0702, GW01-0704 and GW01-0705. As used in this FIG. 17,“H” refers to a 3.75% lower dosage strength imiquimod formulation ofExamples 23-28 and “L” refers to a 2.5% lower dosage strength imiquimodformulation of Examples 23-28.;

FIG. 17A shows a summary of local skin reactions (LSR) area under thecurve of sum of LSR scores (days) for combined studies for an ITTpopulation using either a 2.5% or a 3.75% lower dosage strengthimiquimod formulation of Examples 23-28. The P values are from theanalysis of variance (GLM) including effects of dose, regimen, andanalysis center within regimen. The time period for the AUC extends toeight weeks after the end of treatment for both the two-week treatmentcycle regimen (week 14) and the three-week treatment cycle regimen (week17). Only subjects who receive treatment in both treatment cycles areincluded in this analysis;

FIG. 18 shows safety measures of LSR sum score, by time point, forstudies GW01-0703, GW01-0702, GW01-0704 and GW01-0705;

FIG. 18A shows a mean LSR sum score vs. study time point for two-weektreatment cycle regimens for an ITT population using a 3.75% lowerdosage strength imiquimod formulation of Examples 23-28. Note thefollowing: Bsl=baseline, EoC1=end of cycle 1, SoC2=start of cycle 2,EoC2=end of cycle 2, 4WP=4 weeks post-treatment, 8WP=8 weekspost-treatment, L2=2.5% two-week cycle regimen, H2=3.75% two-weektreatment cycle regimen, P2=placebo two-week treatment cycle regimen;

FIG. 18B shows a mean LSR sum score vs. study time point for three-weektreatment cycle regimens for an ITT population using a 3.75% lowerdosage strength imiquimod formulation of Examples 23-28. Note thefollowing: Bsl=baseline, EoC1=end of cycle 1, SoC2=start of cycle 2,EoC2=end of cycle 2, 4WP=4 weeks post-treatment, 8WP=8 weekspost-treatment, L3=2.5% three-week cycle regimen, H3=3.75% three-weektreatment cycle regimen, P32=placebo three-week treatment cycle regimen;

FIG. 19 shows safety measures of incidence of severe LSR erythema forstudies GW01-0703, GW01-0702, GW01-0704 and GW01-0705. As used in thisFIG. 19, “H” refers to a 3.75% lower dosage strength imiquimodformulation and “L” refers to a 2.5% lower dosage strength imiquimodformulation of Examples 23-28, and “V” refers to vehicle. See also FIGS.16A-C;

FIG. 20 shows mean LSR erythema score, by time point, for studiesGW01-0703, GW01-0702, GW01-0704 and GW01-0705;

FIG. 20A shows LSR mean score vs. study week for erythema for an ITTpopulation for study GW01-0702. As used in this FIG. 20A, “A” refers toa 2.5% lower dosage strength imiquimod formulation, “B” refers to a3.75% lower dosage strength imiquimod formulation of Examples 23-28 andC refers to Placebo;

FIG. 20B shows a LSR mean score vs. study week for erythema for an ITTpopulation for study GW01-0704. As used in this FIG. 20B, “A” refers toa 2.5% lower dosage strength imiquimod formulation, “B” refers to a3.75% lower dosage strength imiquimod formulation of Examples 23-28 andC refers to Placebo;

FIG. 21 shows safety measures of incidence of rest periods for studiesGW01-0703, GW01-0702, GW01-0704 and GW01-0705. See also FIG. 30;

FIG. 22 shows safety measures of rate of study discontinuation, forsafety reasons, for studies GW01-0703, GW01-0702, GW01-0704 andGW01-0705. As used in this FIG. 22, “H” refers to a 3.75% lower dosagestrength imiquimod formulation of Examples 23-28, “L” refers to a 2.5%lower dosage strength imiquimod formulation of Examples 23-28 and “V”refers to vehicle;

FIG. 23 shows a summary of select safety parameters associated withapplications of the 2.5% and 3.75% imiquimod cream formulations ofExample 23 that are used in 2×2×2 week, 2-cycle regimens and used in3×3×3 week 2-cycle regimens. The results demonstrate the overallacceptable safety profile of both the 2.5% and 3.75% imiquimodformulations of Example 23 according to either of the 2 or 3 week cycleregimens. Of note, the safety results suggest a preferable safetyprofile when either the 2.5% or the 3.75% imiquimod formulation is usedin a 2×2×2 week, 2-cycle regimen versus a 3×3×3 week, 2-cycle regimen.

FIG. 24 shows improvement in the Investigator Global integratedphotodamage score from baseline for a two week 2-cycle treatment period(2×2×2 weeks). In this FIG. 24, Study 1 refers to the GW01-0702 studyand Study 2 refers to the GW01-0704 study herein through-out. As used inthis FIG. 24, “Pbo” refers to placebo and “Imiq” refers to imiquimod;

FIG. 25 shows meta-analysis efficacy of pooled clearance rates forstudies GW01-0703, GW01-0702, GW01-0704 and GW01-0705;

FIG. 25A shows a summary of primary and secondary efficacy endpoints forcombined studies, analysis within regimen for an ITT population using a3.75% lower dosage strength imiquimod formulation of Examples 23-28.Complete clearance is defined as the absence of clinically visible orpalpable AK lesions in the treatment area. Partial clearance is definedas at least a 75% reduction in the number of AK lesions in the treatmentarea compared with Baseline. P values are from Cochran-Mantel-Haenszeltest, stratified by analysis site, within regimen, taking 2 treatmentgroups at a time. The P values marked with ** are statisticallysignificant using Hochberg's modified Bonferroni procedure. LOCF=Lastobservation that is carried forward. Confidence intervals are calculatedusing exact binomial statistics;

FIG. 26 shows an efficacy comparison of complete clearance rates, bystudy, for studies GW01-0703, GW01-0702, GW01-0704 and GW01-0705. Asused in this FIG. 26, “2×2×2” refers to a two week, 2-cycle therapy and“3×3×3” refers to a three week, 2-cycle therapy. See also FIG. 25A;

FIG. 27 shows efficacy comparison of partial clearance rates, by study,for studies GW01-0703, GW01-0702, GW01-0704 and GW01-0705. As used inthis FIG. 27, “2×2×2” refers to a two week, 2-cycle therapy and “3×3×3”refers to a three week, 2-cycle therapy. See also FIG. 25A;

FIG. 28 shows safety comparison of incidence of adverse events forstudies GW01-0703, GW01-0702, GW01-0704 and GW01-0705, as compared withAldara® 5% imiquimod cream. As used in this FIG. 28, “2 weeks” refers toa two week, 2-cycle therapy, “3 weeks” refers to a three week, 2-cycletherapy, “Pbo” refers to placebo, “2.5%” refers to a 2.5% imiquimodlower dosage strength formulation of Examples 23-28 and “3.75%” refersto a 3.75% imiquimod lower dosage strength formulation of Examples23-28;

FIGS. 28A-B show a number (%) of subjects in phase 3 studies withtreatment-emergent adverse events with incidence greater than 1% in the3.75% imiquimod two-week treatment cycle group for an ITT population.Counts reflect number of subjects in each treatment group reporting oneor more adverse events that map to the MedDRA system organ class. Asubject may be counted once only in each row of the table. Atreatment-emergent AE is an AE with onset date on or after day 1 oftreatment. As used in these FIGS. 28A-B, “2.5%” refers to a 2.5%imiquimod lower dosage strength formulation of Examples 23-28 and“3.75%” refers to a 3.75% imiquimod lower dosage strength formulation ofExamples 23-28;

FIG. 29 shows a comparison of the incidence of severe erythema [(a localskin reaction (LSR)] for studies GW01-0703, GW01-0702, GW01-0704 andGW01-0705, as compared with Aldara® 5% imiquimod cream. As used in thisFIG. 29, “H” refers to a 3.75% lower dosage strength imiquimodformulation of Examples 23-28, “L” refers to a 2.5% lower dosagestrength imiquimod formulation of Examples 23-28 and “V” refers tovehicle, and “2×2×2” refers to a two week, 2-cycle treatment regimen and“3×3×3” refers to a three week, 2-cycle treatment regimen. See also FIG.16A;

FIG. 30 shows safety measures of incidence of rest periods for studiesGW01-0703, GW01-0702, GW01-0704 and GW01-0705, as compared with Aldara®5% imiquimod cream. As used in this FIG. 30, “H” refers to a 3.75% lowerdosage strength imiquimod formulation of Examples 23-28, “L” refers to a2.5% lower dosage strength imiquimod formulation of Examples 23-28 and“V” refers to vehicle, and “2×2×2” refers to a two week, 2-cycletreatment regimen and “3×3×3” refers to a three week, 2-cycle treatmentregimen. See also FIG. 21;

FIG. 31 shows efficacy measures of clearance rates, by subject sex, forstudies GW01-0703, GW01-0702, GW01-0704 and GW01-0705. See also FIGS.10A-10C;

FIG. 32 shows efficacy measures of clearance rates, by subject age, forstudies GW01-0703, GW01-0702, GW01-0704 and GW01-0705. See also FIGS.10B-10C;

FIG. 32A shows a summary of primary and secondary efficacy endpoints forage subpopulations over and under 65 for combined two-week treatmentcycle studies (GW01-0702 and GW01-0704) for an ITT population for activetreatment only using a 3.75% lower dosage strength imiquimod formulationof Examples 23-28. The P values for clearance rates are from ageneralized linear module (GENMOD), assuming a multinomial distribution(DIST=MULT) and a cumulative logit link function (LINK=CLOGIT),including effects of dose, subpopulation, and interaction. The P valuesfor percent change in AK lesion count are from the analysis of variance(GLM) including effects of dose, subpopulation, and interaction. As usedin this FIG. 32A, “2.5%” refers to a 2.5% imiquimod lower dosagestrength formulation of Examples 23-28, “3.75%” refers to a 3.75%imiquimod lower dosage strength formulation of Examples 23-28., “<65”refers to an age population that is less than 65 years old and “>=65”refers to an age population that is 65 years old or older;

FIG. 33 shows efficacy measures of clearance rates, by subject skintype, for studies GW01-0703, GW01-0702, GW01-0704 and GW01-0705. Seealso FIGS. 10B-10C;

FIG. 33A shows a summary of primary and secondary efficacy endpoints forFitzpatrick skin type subpopulations for combined two-week treatmentcycle studies (GW01-0702 and GW01-0704) for an ITT population for activetreatment only using a 3.75% lower dosage strength imiquimod formulationof Examples 23-28. The P values for clearance rates are from ageneralized linear module (GENMOD), assuming a multinomial distribution(DIST=MULT) and a cumulative logit link function (LINK=CLOGIT),including effects of dose, subpopulation, and interaction. The P valuesfor percent change in AK lesion count are from the analysis of variance(GLM) including effects of dose, subpopulation, and interaction. As usedin this FIG. 33A, “2.5%” refers to a 2.5% imiquimod lower dosagestrength formulation of Examples 23-28, “3.75%” refers to a 3.75%imiquimod lower dosage strength formulation of Examples 23-28, and “I”,“II”, “III”, “IV” “V” or “VI” refer to Fitzpatrick skin type;

FIG. 34 shows efficacy measures of clearance rates, by subject Baselinecount, for studies GW01-0703, GW01-0702, GW01-0704 and GW01-0705. Seealso FIGS. 10B-10C;

FIG. 34A shows a summary of primary and secondary efficacy endpoints forbaseline lesion count subpopulations for combined two-week treatmentcycle studies (GW01-0702 and GW01-0704) for an ITT population for activetreatment only using a 3.75% lower dosage strength imiquimod formulationof Examples 23-28. The P values for clearance rates are from ageneralized linear module (GENMOD), assuming a multinomial distribution(DIST=MULT) and a cumulative logit link function (LINK=CLOGIT),including effects of dose, subpopulation, and interaction. The P valuesfor percent change in AK lesion count are from the analysis of variance(GLM) including effects of dose, subpopulation, and interaction. As usedin this FIG. 34A, “2.5%” refers to a 2.5% imiquimod lower dosagestrength formulation of Examples 23-28 and “3.75%” refers to a 3.75%imiquimod lower dosage strength formulation of Examples 23-28;

FIG. 35 shows efficacy measures of clearance rates, by subject treatmentarea, for studies GW01-0703, GW01-0702, GW01-0704 and GW01-0705. Seealso FIGS. 10B-10C;

FIG. 35A shows a summary of primary and secondary efficacy endpoints forlocation of treatment area (face or balding scalp) subpopulations forcombined two-week treatment cycle studies (GW01-0702 and GW01-0704) foran ITT population for active treatment only using a 3.75% lower dosagestrength imiquimod formulation of Examples 23-28. The P values forclearance rates are from a generalized linear module (GENMOD), assuminga multinomial distribution (DIST=MULT) and a cumulative logit linkfunction (LINK=CLOGIT), including effects of dose, subpopulation, andinteraction. The P values for percent change in AK lesion count are fromthe analysis of variance (GLM) including effects of dose, subpopulation,and interaction. As used in this FIG. 35A, “2.5%” refers to a 2.5%imiquimod lower dosage strength formulation of Examples 23-28, “3.75%”refers to a 3.75% imiquimod lower dosage strength formulation ofExamples 23-28, and “Face” and “Balding Scalp” refer to the treatmentarea;

FIG. 35B shows a summary of primary and secondary efficacy endpoints forlocation of treatment area (face or balding scalp) subpopulations forcombined two-week treatment cycle studies (GW01-0702 and GW01-0704) foran ITT population using a 3.75% lower dosage strength imiquimodformulation of Examples 23-28. The P values for clearance rates are froma generalized linear module (GENMOD), assuming a multinomialdistribution (DIST=MULT) and a cumulative logit link function(LINK=CLOGIT), including effects of dose, subpopulation, andinteraction. The P values for percent change in AK lesion count are fromthe analysis of variance (GLM) including effects of dose, subpopulation,and interaction. As used in this FIG. 35B, “2.5%” refers to a 2.5%imiquimod lower dosage strength formulation of Examples 23-28, “3.75%”refers to a 3.75% imiquimod lower dosage strength formulation ofExamples 23-28, and “Face” and “Balding Scalp” refer to the treatmentarea;

FIG. 36 shows percent complete clearance compared with Aldara® 5%imiquimod cream. In this FIG. 36 and throughout the specification, study1 refers to GW01-0702 study and study 2 refers to GW01-0704 study. Asused in this FIG. 36, “Pbo” refers to placebo, “Imiq” refers toimiquimod, and “Aldara” refers to Aldara® 5% imiquimod cream. See alsoFIG. 1;

FIG. 36A shows percent complete clearance compared with placebo. In thisFIG. 36 and throughout the specification, study 1 refers to GW01-0702study, study 2 refers to GW01-0704 study, study 3 refers to GW01-0703study and study 4 refers to GW01-0705 study. As used in this FIG. 36A,“Pbo” refers to placebo and “Imiq” refers to imiquimod;

FIG. 37 shows percent partial clearance compared with Aldara® 5%imiquimod cream. In this FIG. 37 and throughout the specification, study1 refers to GW01-0702 study and study 2 refers to GW01-0704 study. Asused in this FIG. 37, “Pbo” refers to placebo, “2.5% Imiq” refers to a2.5% imiquimod lower dosage strength formulation of Examples 23-28,“3.75% Imiq” refers to a 3.75% imiquimod lower dosage strengthformulation of Examples 23-28, and “Aldara” refers to Aldara® 5%imiquimod cream. See also FIG. 4A;

FIG. 37A shows a partial clearance compared with placebo. In this FIG.37A and throughout the specification, study 1 refers to GW01-0702 study,study 2 refers to GW01-0704 study, study 3 refers to GW01-0703 study andstudy 4 refers to GW01-0705 study. As used in this FIG. 37A, “Pbo”refers to placebo, “2.5% Imiq” refers to a 2.5% imiquimod lower dosagestrength formulation of Examples 23-28, and “3.75% Imiq” refers to a3.75% imiquimod lower dosage strength formulation of Examples 23-28;

FIG. 38 shows AK median % reduction compared with Aldara® 5% imiquimodcream. In this FIG. 38 and throughout the specification, study 1 refersto GW01-0702 study and study 2 refers to GW01-0704 study. As used inthis FIG. 38, “Pbo” refers to placebo, “2.5% Imiq” refers to a 2.5%imiquimod lower dosage strength formulation of Examples 23-28, “3.75%Imiq” refers to a 3.75% imiquimod lower dosage strength formulation ofExamples 23-28, and “Aldara” refers to Aldara® 5% imiquimod cream;

FIG. 38A shows AK median % reduction compared with placebo. In this FIG.38A and throughout the specification, study 1 refers to GW01-0702 study,study 2 refers to GW01-0704 study, study 3 refers to GW01-0703 study andstudy 4 refers to GW01-0705 study. As used in this FIG. 38A, “Pbo”refers to placebo, “2.5% Imiq” refers to a 2.5% imiquimod lower dosagestrength formulation of Examples 23-28, “3.75% Imiq” refers to a 3.75%imiquimod lower dosage strength formulation of Examples 23-28, and“Aldara” refers to Aldara® 5% imiquimod cream;

FIG. 39 shows rest periods for the 2-cycle, 2×2×2 (2 week) treatmentregimen, as compared with Aldara® 5% imiquimod cream. As used in thisFIG. 39, “Pbo” refers to placebo, “2.5% Imiq” refers to a 2.5% imiquimodlower dosage strength formulation of Examples 23-28, “3.75% Imiq” refersto a 3.75% imiquimod lower dosage strength formulation of Examples23-28, and “Aldara” refers to Aldara® 5% imiquimod cream;

FIG. 39A shows selected safety parameters for combined two-week,two-cycle studies (GW01-0702 and GW01-0704) or three-week, two-cyclestudies (GW01-0703 and GW01-0705). As used in this FIG. 39A, “2.5% Imiq”refers to a 2.5% imiquimod lower dosage strength formulation of Examples23-28, “3.75% Imiq” refers to a 3.75% imiquimod lower dosage strengthformulation of Examples 23-28 and “Tx” refers to treatment;

FIG. 40 shows local skin reactions (“LSRs”); % of subjects with severeLSRs for the 2-cycle, 2×2×2 (2 week) treatment regimen, as compared withAldara® 5% imiquimod cream. As used in this FIG. 40, “Pbo” refers toplacebo, “2.5% Imiq” refers to a 2.5% imiquimod lower dosage strengthformulation of Examples 23-28, “3.75% Imiq” refers to a 3.75% imiquimodlower dosage strength formulation of Examples 23-28, and “Aldara” refersto Aldara® 5% imiquimod cream. See also FIG. 16A-C;

FIG. 41 shows a comparison regarding the incidence of selected commonadverse events for the 2-cycle, 2×2×2 (2 week) treatment regimen, ascompared with Aldara® 5% imiquimod cream. As used in this FIG. 41, “Pbo”refers to placebo, “2.5% Imiq” refers to a 2.5% imiquimod lower dosagestrength formulation of Examples 23-28, “3.75% Imiq” refers to a 3.75%imiquimod lower dosage strength formulation of Examples 23-28, “Aldara”refers to Aldara® 5% imiquimod cream, and “NS” refers to not specified;

FIG. 41A shows incidence of most common (greater than 1%)treatment-related adverse events for combined two-week studies(GW01-0702 and GW01-0704) or three-week studies (GW01-0703 andGW01-0705);

FIG. 42 shows benefit/risk for the 2-cycle, 2×2×2 (2 week) treatmentregimen, as compared with Aldara® 5% imiquimod cream. In this FIG. 42,“Severe ery” refers to severe erythema, “App site rxns” refers toapplication site reactions, “Rest Periods” refers to the percent ofpatients who took rest periods during the study in addition to the twoweek rest period (no treatment period) sandwiched between the 2-cyclesof two week treatments, “Complete Clear” refers to the rate of completeAK lesion clearance, “Partial Clear” refers to the rate of partial AKlesion clearance (defined as at least about 75% reduction in the numberof AK lesions in the treatment area as compared with Baseline), “%Reduction” refers to median percent reduction in AK lesions, “2.5%”refers to a 2.5% imiquimod lower dosage strength formulation of Examples23-28, “3.75%” refers to a 3.75% imiquimod lower dosage strengthformulation of Examples 23-28, and “Aldara” refers to Aldara® 5%imiquimod cream;

FIG. 43 shows a clinical case study of a 39 year old white male in whicha 2.5% imiquimod (IMIQ) formulation is used in a 2 cycle, 2×2×2 weeks,to treat actinic keratosis;

FIG. 44 shows a clinical case study of a 74 year old white male in whicha 2.5% imiquimod (IMIQ) formulation is used in a 2 cycle, 2×2×2 weeks,to treat actinic keratosis;

FIG. 45 shows a clinical case study of a 66 year old white female inwhich a 3.75% imiquimod (IMIQ) formulation is used in a 2 cycle, 2×2×2weeks, to treat actinic keratosis;

FIG. 46 shows a clinical case study of a 73 year old white male in whicha 3.75% imiquimod (IMIQ) formulation is used in a 2 cycle, 2×2×2 weeks,to treat actinic keratosis;

FIG. 47 shows a clinical case study of a 70 year old white male in whicha 2.5% imiquimod (IMIQ) formulation is used in a 2 cycle, 3×3×3 weeks totreat actinic keratosis;

FIG. 48 shows a clinical case study of a 65 year old white female inwhich a 2.5% imiquimod (IMIQ) formulation is used in a 2 cycle, 3×3×3weeks to treat actinic keratosis;

FIG. 49 shows a clinical case study of a 79 year old white male in whicha 3.75% imiquimod (IMIQ) formulation is used in a 2 cycle, 3×3×3 weeksto treat actinic keratosis;

FIG. 50 shows a clinical case study of a 78 year old white male in whicha 3.75% imiquimod (IMIQ) formulation is used in a 2 cycle, 3×3×3 weeksto treat actinic keratosis; and

FIG. 51 shows a summary of primary and secondary efficacy endpoints inwhich (a) the results of the GW01-0702 and GW01-0704 (2×2×2) studies foreach imiquimod formulation strength, i.e., about 2.5% or about 3.75%w/w, that are used in the studies are combined, respectively, (b) theresults of the GW01-0703 and GW01-0705 (3×3×3) studies for eachimiquimod formulation strength, i.e., about 2.5% or about 3.75% w/w,that are used in the studies are combined, respectively, and (c) theanalysis is within regimen ITT populations. Complete clearance isdefined as the absence of clinically visible or palpable AK lesions inthe treatment area. Partial clearance is defined as at least about a 75%reduction in the number of AK lesions in the treatment area as comparedwith Baseline. P values are from Cochran-Mantel-Haenszel test, arestratified by analysis site, within regimen, taking 2 treatment groupsat a time. The P values that are marked with ** are statisticallysignificant using Hochberg modified Bonferroni procedure. LOCF=lastobservation carried forward. Confidence intervals are calculated usingexact binomial statistics. In this FIG. 51, “2.5%” refers to a 2.5%imiquimod lower dosage strength formulation of Examples 23-28 and“3.75%” refers to a 3.75% imiquimod lower dosage strength formulation ofExamples 23-28. See also FIG. 25A;

FIG. 52 shows a summary of primary and secondary efficacy endpoints fromcombined studies and an analysis across regimens for the ITT Population.Column (1) P values for all parameters are from the analysis of variancebased on a General Linear Model (“GLM”) including effects of dose,regimen, and analysis site within regimen. Column (2) P values are basedon a logistic analysis of the effects of dose, regimen, and analysissite. In this FIG. 52, “2.5%” refers to a 2.5% imiquimod lower dosagestrength formulation of Examples 23-28 and “3.75%” refers to a 3.75%imiquimod lower dosage strength formulation of Examples 23-28;

FIG. 53 shows a summary of an Investigators Global IntegratedPhotodamage (“IGIP”) score for the (a) GW01-0702 and GW01-0704 studies,(b) GW01-0703 and GW01-0705 studies and (c) combined studies, i.e.,GW01-0702, GW01-0703, GW01-0704 and GW01-0705 studies, for a two-week2-cycle treatment period (2×2×2 weeks) and a three-week 2-cycletreatment period (3×3×3 weeks) for the Intent-To-Treat (“ITT”)population. In this FIG. 53, “2.5%” refers to a 2.5% imiquimod lowerdosage strength formulation of Examples 23-28 and “3.75%” refers to a3.75% imiquimod lower dosage strength formulation of Examples 23-28;

FIG. 54 shows a summary of serum pharmacokinetic parameters at day 21for a 3.75% imiquimod formulation of Examples 23-28, PK population. Theserum analyte is imiquimod. The calculation of accumulation ratio (RAUC,RCmax) and effective half-life for accumulation (T½ and T½ eff), isrestricted to subjects who take all seven doses during the week oftreatment and who take at least 80% of the prescribed doses during theprior two weeks. The PK parameters are not calculated for subject001-619 and subject 001-608. There is no concentration data for subject001-619, and subject 001-608 did not take all required doses during the21 days of treatment. AUC₀₋₂₄ equals AUCss and C_(min) equals predoseconcentration (t=0). In this FIG. 51, “Imiquimod” refers to a 3.75%imiquimod lower dosage strength formulation of Examples 23-28. See alsoExample 25;

FIG. 55 shows a calibrated graticule scale at ×400 magnification; wherethe 10 μm, 50 μm and 100 μm divisions are indicated;

FIG. 56 shows a schematic representation of a Franz cell;

FIG. 57 shows a summary of microscope pictures of eight 2.5% w/wimiquimod formulations, i.e., formulations 113, 246, 247, 248, 249, 251,252 and 253 (the formulations continued into the stability program areincluded for the 1 kg batches in TABLE 18 and FIG. 64);

FIG. 58 shows a comparison of the mean cumulative amount of imiquimodreleased (μg/cm2) after about 3 h for the membrane release studies (forall the formulations selected for Full thickness skin permeation andstability studies) (mean±sd, where n=4);

FIG. 59 shows a comparison of the average total cumulative reportreleased (μg/cm2) after 3 h for each concentration of imiquimod in theformulations that are tested (mean□sd, where n=4 for 1%, n=16 for 2.5%,n=20 for 3.75% and n=12 for 5%);

FIG. 60. shows a total amount of imiguimod that is recovered followingmass balance for each formulation (See also Tables 35-40 for statisticalanalysts) (mean±sd, refer to Table 34 for n numbers of each sample);

FIG. 61 shows a total amount of imiquimod recovered for each formulationin the receiver fluid, epidermis and dermis combined (mean±sd, refer toTable 34 for n numbers of each sample);

FIG. 62 shows a total amount of imiquimod recovered for the averages ofeach imiquimod concentration from each of the skin matrices.

FIGS. 63A-C show microscopic depiction of 13 imiquimod formulations,i.e., 3M Aldara® imiquimod cream 1 kg batch, Graceway 3M Aldara®imiquimod cream 1 kg batch and formulations 110, 123, 125, 126, 182,183, 195, 197, 250, 256 and 257 (t=0, 1, 2, 3 and 6 months)—×400magnification;

FIG. 64 shows microscopic depiction of placebo formulations Pbo1-Pbo4(t=0, 1, 2, 3 and 6 months)—×400 magnification;

FIGS. 65A-B show microscopic depiction of 10 imiquimod formulations,i.e., formulations, 116, 117, 254, 120, 235, 188, 189, 184, 255, 124,after 1 month stability (t=0 and 1 month)—×400 magnification;

FIG. 66 shows a comparison of the mean amount of imiquimod that isreleased (μg/cm2) over a 3 hour period for the 3M Aldara® imiquimodcream 1 kg batch, the 3M Aldara® imiquimod cream sachet, the Graceway 3MAldara® imiquimod cream 1 kg batch and formulation 257, a 1% Imiquimodformulation (mean±sd, where n=4);

FIG. 67 shows a comparison of the mean amount of imiquimod that isreleased (μg/cm2) over a 3 hour period for four 2.5% imiquimodformulations, i.e., formulations 110, 123, 125 and 250 (mean±sd, wheren=4).

FIG. 68 shows a comparison of the mean amount of imiquimod that isreleased (μg/cm2) over a 3 hour period for five 3.75% imiquimodformulations, i.e., formulations 182, 183, 195, 197 and 256 (mean±sd,where n=4); and

FIG. 69 shows a comparison of the mean amount of imiguimod released(μg/cm²) over a 3 hour period for the 2.5% (▴), 3.75% (), 3M Aldara®imiquimod cream batch (

), Graceway Aldara® imiquimod cream 1 kg batch (▪) and formulation 257Imiquimod formulations (

) (mean±sd, where n=4).

FIG. 70 includes flow diagrams illustrating the treatment regimen forstudies GW01-0702, GW01-0703, GW01-0704 and GW01-0705.

DETAILED DESCRIPTION OF THE INVENTION

By way of illustrating and providing a more complete appreciation of thepresent invention and many of the attendant advantages thereof, thefollowing detailed description and examples are given concerning thenovel methods and compositions.

In general, the present invention relates to a pharmaceuticalcomposition comprising imiquimod and a pharmaceutically acceptablevehicle for imiquimod, which vehicle comprises a fatty acid. While thepresent invention may be embodied in many different forms, severalspecific embodiments are discussed herein with the understanding thatthe present disclosure is to be considered only as an exemplification ofthe principles of the invention, and it is not intended to limit theinvention to the embodiments described or illustrated.

As used in the specification and claims, the phrase “substantiallyless-irritating” designates formulations that do not cause unacceptableskin irritation in conventional repeat skin irritation tests in albinorabbits such as that described in Draize et al., “Appraisal of theSafety of Chemicals in Food, Drugs and Cosmetics”, prepared by theDivision of Pharmacology of the Food and Drug Administration, publishedoriginally in 1959 by the Association of Food and Drug Officials of theUnited States, Topeka, Kans. (2nd printing 1965), incorporated herein byreference.

Unless otherwise indicated, all numbers expressing quantities, ratios,and numerical properties of ingredients, reaction conditions, and soforth used in the specification and claims are to be understood as beingmodified in all instances by the term “about”. All parts, percentages,ratios, etc. herein are by weight unless indicated otherwise.

As used herein, the singular forms “a” or “an” or “the” are usedinterchangeably and intended to include the plural forms as well andfall within each meaning, unless expressly stated otherwise. Also asused herein, “at least one” is intended to mean “one or more” of thelisted element. Singular word forms are intended to include plural wordforms and are likewise used herein interchangeably where appropriate andfall within each meaning, unless expressly stated otherwise. Exceptwhere noted otherwise, capitalized and non-capitalized forms of allterms fall within each meaning.

By the term “bioequivalence or bioequivalent”, as used herein, it refersto lower dosage strength formulations in which they are pharmaceuticallyequivalent and their bioavailibilities (rate and extent of absorption)after administration in the same molar dosage or amount are similar tosuch a degree that their therapeutic effects, as to safety and efficacy,are essentially the same. In other words, bioequivalence orbioequivalent means the absence of a significant difference in the rateand extent to which imiquimod becomes available from such formulationsat the site of imiquimod action when administered at the same molar doseunder similar conditions, e.g., the rate at which imiquimod can leavesuch a formulation and the rate at which imiquimod can either cross thestratum corneum and/or become available at the site of action to treatactinic keratosis. In other words, there is a high degree of similarityin the bioavailabilities of two imiquimod pharmaceutical products (ofthe same galenic form) from the same molar dose, that are unlikely toproduce clinically relevant differences in therapeutic effects, oradverse reactions, or both. The terms “bioequivalence”, as well as“pharmaceutical equivalence” and “therapeutic equivalence” are also usedherein as defined and/or used by (a) the FDA, (b) the Code of FederalRegulations (“C.F.R.”), Title 21, and/or (c) Health Canada.

By the term “bioavailability or bioavailable”, as used herein, it meansgenerally the rate and extent of absorption of imiquimod into thesystemic circulation and, more specifically, the rate or measurementsintended to reflect the rate and extent to which imiquimod becomesavailable at the site of action or is absorbed from a drug product andbecomes available at the site of action. In other words, and by way ofexample, the extent and rate of imiquimod absorption from a lower dosagestrength formulation of the present invention as reflected by atime-concentration curve of imiquimod in systemic circulation.

By “pharmaceutical equivalence or pharmaceutically equivalent”, as usedherein, it refers to lower dosage strength imiquimod formulations of thepresent invention that contain the same amount of imiquimod, in the samedosage forms, but not necessarily containing the same inactiveingredients, for the same route of administration and meeting the sameor comparable compendial or other applicable standards of identity,strength, quality, and purity, including potency and, where applicable,content uniformity and/or stability.

By “therapeutic equivalence or therapeutically equivalent”, it is meantherein to mean those lower dosage strength imiquimod formulations which(a) will produce the same clinical effect and safety profile whenpracticing the short durations of therapy to treat actinic keratosis inaccordance with the present invention and (b) are pharmaceuticalequivalents, e.g., they contain imiquimod in the same dosage form, theyhave the same route of administration; and they have the same imiquimodstrength. In other words, therapeutic equivalence means that a chemicalequivalent of an imiquimod lower dosage strength imiquimod formulationof the present invention (i.e., containing the same amount of imiquimodin the same dosage form) when administered to the same individuals inthe same dosage regimen will provide essentially the same efficacy andtoxicity.

By “T_(max)”, it is meant herein to mean the time when the maximumimiquimod serum concentration is reached at steady state followingtopical application of a lower dosage strength imiquimod formulation ofthe present invention, i.e., when the rate of imiquimod absorptionequals the rate of imiquimod elimination. In other words, the time thatC_(max) is observed for imiquimod.

By “C_(max)”, it is meant herein to refer to the maximum imiquimod serumconcentration that is reached at steady state following topicalapplication of a lower dosage strength imiquimod formulation of thepresent invention, i.e., when the rate of imiquimod absorption equalsthe rate of imiquimod elimination. In other words, it is the maximumserum concentration; the highest serum concentration observed during theimiquimod dosing or sampling interval.

By “C_(min)”, it is meant herein to refer to the minimum measurableimiquimod serum concentration; e.g., imiquimod serum concentration thatis observed immediately prior to dosing on Days 7, 14, 21 and 22 (24hours post-dose).

By “T_(1/2)”, it is meant herein to mean the time required for half ofthe quantity of maximum imiquimod serum concentration to be eliminatedonce steady state is achieved following topical application of a lowerdosage strength imiquimod formulation of the present invention. Forexample, the apparent elimination half-life for imiquimod, that iscalculated as about 0.693/λ_(Z) in accordance with Example 24.

By “AUC₀₋₂₄”, it is meant herein to mean the area under the serumimiquimod concentration versus a 24 hour time curve following topicalapplication of a lower dosage strength imiquimod formulation of thepresent invention, i.e., a measure of imiquimod exposure over a 24 hourperiod. For example, the area under the imiquimod serum concentrationversus time curve, from 0 to 24 hours, that is calculated using thelinear trapezoid rule or extrapolated to 24 hours in cases wherereportable values are not obtainable up to that time point.

By “AUC_(0-t)”, it is meant herein to mean the area under the imiquimodserum concentration versus time curve, from 0 to the time of the lastnon-zero concentration on Day 1; that is calculated using the lineartrapezoid rule.

By “R_(AUC)”, it is meant herein to mean the accumulation ratio; thatare calculated as the AUC₀₋₂₄ value during multiple-imiquimod doseadministration divided by the AUC₀₋₂₄ value following the first dose(i.e., Day 21/Day 1); or the accumulation ratios that are calculated foran imiquimod metabolite only if sufficient non-zero time points areavailable to reasonably estimate AUC₀₋₂₄.

By “AUC_(0-inf)”, it is meant herein to mean the area under theimiquimod serum concentration versus time curve, from 0 to infinity;AUC_(0-inf) that is calculated on Day 1 asAUC_((0-inf))=AUC_((0-t))+Ct/K_(el) (where C_(t)=the fitted lastnon-zero concentration, AUC_(0-t)=the AUC from time zero to the time ofthe last non-zero concentration and K_(el)=the elimination rateconstant).

By “R_(Cmax)”, it is meant herein to mean the accumulation ratio;calculated as the C_(max) value during multiple-dose administrationdivided by the C_(max) value following the first dose (i.e., Day 21/Day1)

By “λ_(z EFF”), it is meant herein to mean the effective eliminationrate constant, calculated as −ln(1−1/R_(AUC))/tau.

By “T_(1/2 EFF)”, it is meant herein to mean the effective half-life foraccumulation; calculated as 0.693/λ_(z EFF).

By “λz”, it is meant to refer to an elimination rate constant, i.e., therate at which imiquimod disappears from the site of measurement oncesteady state is achieved following topical application of a lower dosagestrength imiquimod formulation of the present invention. In other words,the apparent elimination rate constant; that is calculated using linearregression on the terminal portion of the In concentration versus timeprofile.

By “geometric mean”, it refers a statistical average of a set oftransformed numbers often used to represent a central tendency in highlyvariable data. It is calculated from data transformed using powers orlogarithms and then transformed back to original scale after averaging.

By “geometric mean ratio”, it refers to a ratio of two geometric means,where the “geometric LS mean test” is the numerator of the geometricmean ratio, and the “geometric LS mean reference” is the denominator ofthe geometric mean ratio.

By “RH”, it refers herein to relative humidity.

By “cPs, it refers herein to centipoise.

By “h”, it refers herein to hours.

By “ITT”, it refers to an intent-to-treat population.

By “Pbo, it refers to placebo.

By “EOS”, it refers to End of Study.

By “V”, it refers to vehicle.

Studies GW01-0702 and GW01-0704 are duplicative studies that investigate2-week treatment cycles, wherein the 2-week treatment cycles areseparated by a two week rest period (no treatment) (2×2×2), and studiesGW01-0703 and GW01-0705 are duplicative studies that investigate 3-weektreatment cycles, wherein the 3-week treatment cycles are separated by athree week rest period (no treatment) (3×3×3). See Table 64 herein belowand the flow diagrams depicted in FIG. 70.

By “L2”, it refers to a 2.5% lower dosage strength imiquimod formulationthat is described in Examples 23-28 and the FIGS. and that is used inconnection with studies GW01-0702 and GW01-0704.

By “L3”, it refers to a 3.75% lower dosage strength imiquimodformulation that is described in Examples 23-28 and the FIGS. and thatis used in connection with studies GW01-0702 and GW01-0704.

By “H2”, it refers to a 2.5% lower dosage strength imiquimod formulationthat is described in Examples 23-28 and the FIGS. and that is used inconnection with studies GW01-0703 and GW01-0705.

By “H3”, it refers to a 3.75% lower dosage strength imiquimodformulation that is described in Examples 23-28 and the FIGS. and thatis used in connection with studies GW01-0703 and GW01-0705.

By “AE”, it refers herein to adverse events.

By “2×2×2”, as used herein, it refers to a two-week, 2-cycle AKtreatment regimen, wherein (1) during the first 2 weeks (the first cycleof treatment), a lower dosage strength imiquimod formulation of thepresent invention is applied once daily each day to an AK treatmentarea, (2) during the second 2 weeks, there is a rest period in which notreatment occurs, and (3) during the third 2 weeks (the second cycle oftreatment), the same formulation is again applied once daily each day tothe same AK treatment area, In other words, during the first 2 weeks,treatment is on, during the second 2 weeks, treatment is off, and duringthe third 2 weeks, treatment is on again,

By “3×3×3”, as used herein, it refers to a three-week, 2-cycle AKtreatment regimen, wherein (1) during the first 3 weeks (the first cycleof treatment), a lower dosage strength imiquimod formulation of thepresent invention is applied once daily each day to an AK treatmentarea, (2) during the second 3 weeks, there is a rest period in which notreatment occurs, and (3) during the third 3 weeks (the second cycle oftreatment), the same formulation is again applied once daily each day tothe same AK treatment area, In other words, during the first 3 weeks,treatment is on, during the second 3 weeks, treatment is off, and duringthe third 3 weeks, treatment is on again,

The present invention provides pharmaceutical formulations such ascreams, ointments, foams, gels, lotions and adhesive coatings thatcontain imiquimod and a fatty acid such as isostearic, linoleic,unrefined oleic acid, refined oleic acid, such as Super Refined® oleicacid NF (e.g., a highly purified oleic acid, i.e., an oleic acid whichhas low polar impurities, such as peroxides, a low peroxide value and ismarketed by CRODA; see e.g., www.crodausa.com) and mixtures thereof. Theformulations of the invention provide desirable skin penetrability ofthe imiquimod.

The compound imiquimod is a known antiviral agent that is also known toinduce interferon biosynthesis. It can be prepared using the methoddisclosed in U.S. Pat. No. 4,689,338, the disclosure of which isincorporated herein by reference in its entirety. The compound can beused to treat actinic keratosis. The amount of imiquimod present in aformulation of the present invention will be an effective amount totreat actinic keratosis to achieve total AK lesion clearance or partialAK lesion reduction or clearance, to prevent the recurrence of such adisease and/or to promote immunity against such a disease with anacceptable safety profile. An example of an effective amount ofimiquimod in a formulation of the present invention is between about 1.0percent and about 4.25 percent by weight based on the total weight of aformulation, more preferably between about 1.5%, 1.75%, 2.0%, 2.25%,2.5%, 2.75%, 3.0%, 3.25%, 3.5%, 3.75%, 4.0% and 4.25%, even morepreferably between about 2.0%, 2.25%, 2.5%, 2.75%, 3.0%, 3.25%, 3.5%,3.75% and 4.0%, and still even more preferably between about 2.5%,2.75%, 3.0%, 3.25%, 3.5% and 3.75%. Imiquimod formulations of thepresent invention that contain about 2.5% imiquimod or about 3.75%imiquimod by weight based on the total weight of the formulation aremost preferred.

Likewise, a shortened period or duration, as contemplated by the presentinvention, will be for reduced periods of time effective to treatactinic keratosis as discussed herein above, e.g., up to six weeks,again depending upon the lower dosage strength imiquimod formulation ofthe present invention that is selected for daily application, andpreferably up to four weeks. By way of example, short periods oftreatment with lower dosage strength imiquimod formulations for treatingactinic keratosis, include:

(a) applying an effective amount of imiquimod, such as via the lowerdosage strength imiquimod formulations of the present invention to thearea affected with actinic keratosis, as follows: applying an effectiveamount once per day for fourteen (14) consecutive days, followed by arest period of for fourteen (14) days (no treatment), followed by againapplying an effective amount once per day for fourteen (14) days for atotal of twenty-eight (28) doses or four weeks to treat actinickeratosis (2-cycle therapy); or

(b) applying an effective amount of imiquimod, such as via the lowerdosage strength imiquimod formulations of the present invention to thearea affected with actinic keratosis, as follows: applying an effectiveamount once per day for twenty one (21) days, followed by a rest periodof twenty one (21) days (no treatment, followed by again applying aneffective amount once per day for twenty one (21) consecutive days for atotal of forty-two (42) doses or six weeks to treat actinic keratosis(2-cycle therapy); or

(c) applying an effective amount of imiquimod, such as via a suitablelower dosage strength imiquimod formulation of the present invention tothe area affected with actinic keratosis, once per day for up to aboutforty-two (42) days or less and, preferably, for up to abouttwenty-eight days (28) or less (1-cycle therapy).

A fatty acid such as isostearic acid, palmitic acid, stearic acid,linoleic acid, refined oleic acid, such as Super Refined® oleic acid NF(e.g., a highly purified oleic acid, i.e., an oleic acid which has lowpolar impurities, such as peroxides, a low peroxide value and ismarketed by CRODA; see e.g., www.crodausa.com), an unrefined oleic acidblended with effective amounts of antioxidants or mixtures thereof areincorporated into formulations of the present invention. The totalamount of fatty acid present in a formulation is preferably betweenabout 3 percent and about 45 percent by weight based on the total weightof a formulation. It should be understood that when oleic acid isselected as a fatty acid, that stability may present issue. Thus,stabilizers, such as anti-oxidants and the like, may be required topreserve pharmaceutical elegance and stability over the life of theoleic acid formulation.

A pharmaceutical formulation of the invention can be in a form such as acream, an ointment, a foam, a gel, a lotion, a pressure-sensitiveadhesive composition, or other forms known to those skilled in the art,each particular form containing imiquimod and fatty acid in particularamounts, and optionally containing various additional elements. Thepreferred amounts of drug and fatty acid, and the amounts and types ofoptional elements used in formulations of the invention are discussedbelow with particular reference to creams, ointments and adhesivecompositions.

A cream according to the invention contains1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine and fatty acid.

The amount of 1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine present in acream is preferably about 0.5 percent to about 9 percent by weight, andmore preferably about 1 percent to about 5 percent by weight, based onthe total weight of the cream.

The total amount of fatty acid present in a cream of the invention ispreferably about 3 percent to about 45 percent by weight, and morepreferably about 5 percent to about 25 percent by weight, based on thetotal weight of the cream.

Optionally, a cream of the present invention can contain emollients,emulsifiers, thickeners, and/or preservatives.

Emollients such as long chain alcohols, e.g., cetyl alcohol, stearylalcohol and cetearyl alcohol; hydrocarbons such as petrolatum and lightmineral oil; or acetylated lanolin can be included in a cream of theinvention. A cream can contain one or more of these emollients. Thetotal amount of emollient in a cream of the invention is preferablyabout 5 percent to about 30 percent, and more preferably about 5 percentto about 10 percent by weight based on the total weight of the cream.

Emulsifiers such as nonionic surface active agents, e.g., polysorbate 60(available from ICI Americas), sorbitan monostearate, polyglyceryl-4oleate, and polyoxyethylene(4)lauryl ether or trivalent cationic a creamof the invention. A cream can contain one or more emulsifiers. Generallythe total amount of emulsifier is preferably about 2 percent to about 14percent, and more preferably about 2 percent to about 6 percent byweight based on the total weight of the cream.

Pharmaceutically acceptable thickeners, such as Xanthum gum, Guar gum,Veegum Gum™K (available from R. T. Vanderbilt Company, Inc.), and longchain alcohols (i.e. cetyl alcohol, stearyl alcohol or cetearyl alcohol)can be used. A cream can contain one or more thickeners. The totalamount of thickener present is preferably about 3 percent to about 12percent by weight based on the total weight of the cream.

Preservatives such as methylparaben, propylparaben and benzyl alcoholcan be present in a cream of the invention. The appropriate amount ofsuch preservative(s) is known to those skilled in the art.

Optionally, an additional solubilizing agent such as benzyl alcohol,lactic acid, acetic acid, stearic acid, salicylic acid, anyalpha-hydroxy acid such as glycolic acid, or hydrochloric acid can beincluded in a cream of the invention.

If an additional solubilizing agent is used, the amount present ispreferably about 1 percent to about 12 percent by weight based on thetotal weight of the cream.

Optionally, a cream of the invention can contain a humectant such asglycerin, skin penetration enhancers such as butyl stearate, andadditional solubilizing agents.

Generally, a cream consists of an oil phase and a water phase mixedtogether to form an emulsion. Preferably, the amount of water present ina cream of the invention is about 45 percent to about 85 percent byweight based on the total weight of the cream. The oil phase of a creamof the invention can be prepared by first combining the1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine or1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine and the fatty acid(if the cream contains benzyl alcohol it can also be added at thispoint) and heating with occasional stirring to a temperature of about50° C. to 85° C. When the 1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amineor 1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine appears to becompletely dissolved, the remaining oil phase ingredients are added andheating is continued until dissolution appears to be complete.

The water phase can be prepared by combining all other ingredients andheating with stirring until dissolution appears to be complete.

The creams of the invention are generally prepared by adding the waterphase to the oil phase with both phases at a temperature of about 65° C.to 75° C. The resulting emulsion is mixed with a suitable mixerapparatus to give the desired cream.

An ointment of the invention contains an ointment base in addition to1-isobutyl-1H-itnidazo[4,5-c]quinolin-4-amine and fatty acid.

The amount of 1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine present inan ointment of the invention is preferably about 0.5 percent to about 9percent, and more preferably about 0.5 percent to about 5 percent byweight based on the total weight of the ointment.

The total amount of fatty acid present in an ointment of the inventionis preferably about 3 percent to about 45 percent, and more preferablyabout 3 percent to about 25 percent based on the total weight of theointment.

A pharmaceutically acceptable ointment base such as petrolatum orpolyethylene glycol 400 (available from Union Carbide) in combinationwith polyethylene glycol 3350 (available from Union Carbide) can beused. The amount of ointment base present in an ointment of theinvention is preferably about 60 percent to about 95 percent by weightbased on the total weight of ointment.

Optionally, an ointment of the invention can also contain emollients,emulsifiers and thickeners. The emollients, emulsifiers, and thickenersand the preferred amounts thereof described above in connection withcreams are also generally suitable for use in an ointment of theinvention.

An ointment according to the invention can be prepared by combining1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine with fatty acid and heatingwith occasional stiffing to a temperature of about 65° C. When the1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine or1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine appears to becompletely dissolved, the remaining ingredients are added and heated toabout 65.° C. The resulting mixture is mixed with a suitable mixer whilebeing allowed to cool to room temperature.

A pressure-sensitive adhesive composition of the invention contains1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine or1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine, fatty acid, and apressure sensitive adhesive polymer.

The amount of 1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine or1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine present in apressure sensitive adhesive composition of the invention is preferablyabout 0.5 percent to about 9 percent by weight, and more preferablyabout 3 percent to about 7 percent by weight based on the total weightof the adhesive composition. The amount of fatty acid present ispreferably about 10 percent to about 40 percent by weight, morepreferably about 15 percent to about 30 percent by weight, and mostpreferably about 20 percent to about 30 percent by weight, based on thetotal weight of the adhesive composition.

Preferably, the adhesive polymer utilized in a pressure sensitiveadhesive composition of the invention is substantially chemically inertto 1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine or1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine. The adhesivepolymer is preferably present in an amount of about 55 percent to about85 percent by weight based on the total weight of the composition.Suitable adhesive polymers include acrylic adhesives that contain, as amajor constituent (i.e., at least about 80 percent by weight of allmonomers in the polymer), a hydrophobic monomeric acrylic or methacrylicacid ester of an alkyl alcohol, the alkyl alcohol containing 4 to 10carbon atoms. Examples of suitable monomers are those discussed below inconnection with the “A Monomer”. These adhesive polymers can furthercontain minor amounts of other monomers such as the “B Monomers” listedbelow.

Preferred adhesives include acrylic pressure-sensitive adhesivecopolymers containing A and B Monomers as follows: Monomer A is ahydrophobic monomeric acrylic or methacrylic acid ester of an alkylalcohol, the alkyl alcohol containing 4 to 10 carbon atoms, preferably 6to 10 carbon atoms, more preferably 6 to 8 carbon atoms, and mostpreferably 8 carbon atoms. Examples of suitable A Monomers are n-butyl,n-pentyl, n-hexyl, isoheptyl, n-nonyl, n-decyl, isohexyl, 2-ethyloctyl,isooctyl and 2-ethylhexyl acrylates. The most preferred A Monomer isisooctyl acrylate.

Monomer B is a reinforcing monomer selected from the group consisting ofacrylic acid; methacrylic acid; alkyl acrylates and methacrylatescontaining 1 to 3 carbon atoms in the alkyl group; acrylamide;methacrylamide; lower alkyl-substituted acrylamides (i.e., the alkylgroup containing 1 to 4 carbon atoms) such as tertiary-butyl acrylamide;diacetone acrylamide; n-vinyl-2-pyrrolidone; vinyl ethers such as vinyltertiary-butyl ether; substituted ethylenes such as derivatives ofmaleic anhydride, dimethyl itaconate and monoethyl formate and vinylperfluoro-n-butyrate. The preferred B Monomers are acrylic acid,methacrylic acid, the above-described alkyl acrylates and methacrylates,acrylamide, methacrylamide, and the above-described lower alkylsubstituted acrylamides. The most preferred B Monomer is acrylamide.

In one embodiment of a pressure-sensitive adhesive composition of theinvention, the pressure-sensitive adhesive copolymer containing A and BMonomers as set forth above preferably contains the A Monomer in anamount by weight of about 80 percent to about 98 percent of the totalweight of all monomers in the copolymer. The A Monomer is morepreferably present in an amount by weight of about 88 percent to about98 percent, and is most preferably present in an amount by weight ofabout 91 percent to about 98 percent. The B Monomer in such a copolymeris preferably present in the pressure-sensitive adhesive copolymer in anamount by weight of about 2 percent to about 20 percent, more preferablyabout 2 percent to about 12 percent, and most preferably 2 to 9 percentof the total weight of the monomers in the copolymer.

In another embodiment of a pressure-sensitive adhesive composition ofthe invention, the adhesive copolymer comprises about 60 to about 80percent by weight (and preferably about 70 to about 80 percent byweight) of the above-mentioned hydrophobic monomeric acrylic ormethacrylic acid ester of an alkyl alcohol (i.e., Monomer A describedabove) based on the total weight of all monomers in the copolymer; about4 to about 9 percent by weight based on the total weight of all monomersin the copolymer of a reinforcing monomer selected from the groupconsisting of acrylic acid, methacrylic acid, an alkyl acrylate ormethacrylate containing 1 to 3 carbon atoms in the alkyl group,acrylamide, methacrylamide, a lower alkyl-substituted acrylamide,diacetone acrylamide and N-vinyl-2-pyrrolidone; and about 15 to about 35percent by weight (and preferably about 15 to about 25 percent byweight) of vinyl acetate based on the total weight of all monomers inthe copolymer. In this embodiment the preferred acrylic or methacrylicacid ester is isooctyl acrylate and the preferred reinforcing monomer isacrylamide.

The above described adhesive copolymers are known, and methods ofpreparation therefore are well known to those skilled in the art, havingbeen described for example, in U.S. Pat. No. 24,906 (Ulrich), thedisclosure of which is incorporated herein by reference. Thepolymerization reaction can be carried out using a free radicalinitiator such as an organic peroxide (e.g., benzoylperoxide) or anorganic azo compound (e.g., 2,2′-azobis(2,4-dimethylpentanenitrile),available under the trade designation “Vazo 52” from DuPont).

Since pressure-sensitive adhesives such as those described above areinherently rubbery and tacky and are suitably heat and light stable,there is no need to add tackifiers or stabilizers. However, such can beadded if desired.

Optionally, a pressure sensitive adhesive composition of the inventioncan also contain one or more skin penetration enhancers such as glycerylmonolaurate, ethyl oleate, isopropyl myristate, diisopropyl adipate andN,N-dimethyldodecylamine-N-oxide, either as a single ingredient or as acombination of two or more ingredients. The skin penetration enhancer(s)preferably form a substantially homogeneous mixture with the pressuresensitive adhesive polymer or copolymer. The total amount of skinpenetration enhancer(s) present in a pressure sensitive adhesivecomposition of the invention is preferably about 3 percent to about 25percent by weight, more preferably about 3 percent to about 10 percentby weight based on the total weight of the adhesive composition.

When the skin penetration enhancer is a single ingredient, it ispreferably a skin penetration enhancer such as isopropyl myristate,diisopropyl adipate, ethyl oleate, or glyceryl monolaurate.

When a combination skin penetration enhancer is used, it is preferably acombination such as: ethyl oleate with glyceryl monolaurate; ethyloleate with N,N-dimethyldodecylamine-N-oxide; glyceryl monolaurate withN,N-dimethyldodecylamine-N-oxide; and ethyl oleate with both glycerylmonolaurate and N,N-dimethyldodecylamine-N-oxide.

A pressure-sensitive adhesive composition of the invention can beprepared by combining dry adhesive,1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine, fatty acid, and skinpenetration enhancer(s) with an organic solvent. The preferred organicsolvents are methanol and ethyl acetate. The total solids content of theadhesive coating is preferably in the range of about 15 percent to about40 percent, and more preferably in the range of about 20 to about 35percent based on the total weight of the adhesive coating. The resultingmixture is shaken or mixed for a period of about 20 to 72 hours. Whenthis method is used it is preferred that the1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine be in micronized form(i.e., particle size of 1-2 microns in diameter). Optionally, themixture can be heated during shaking.

In a preferred method, the 1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amineor 1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine is combined withthe fatty acid and shaken at 40° C. until there appears to be completedissolution. The remaining ingredients are added and the mixture isshaken for a period of about 20 to 72 hours.

The pressure-sensitive adhesive compositions described above arepreferably coated onto one surface of a suitable backing of sheetmaterial, such as a film, to form a pressure-sensitive adhesive coatedsheet material. A pressure-sensitive adhesive coated sheet material ofthe invention can be prepared by knife coating a suitable release linerto a predetermined uniform thickness with a wet adhesive formulation.This adhesive coated release liner is then dried and laminated onto abacking using conventional methods. Suitable release liners includeconventional release liners comprising a known sheet material, such as apolyester web, a polyethylene web, or a polystyrene web, orpolyethylene-coated paper, coated with a suitable silicone-type coatingsuch as that available under the trade designation Daubert 164Z, fromDaubert Co. The backing can be occlusive, non-occlusive or a breathablefilm as desired. The backing can be any of the conventional materialsfor pressure-sensitive adhesive tapes, such as polyethylene,particularly low density polyethylene, linear low density polyethylene,high density polyethylene, randomly-oriented nylon fibers,polypropylene, ethylene-vinylacetate copolymer, polyurethane, rayon andthe like. Backings that are layered, such aspolyethylene-aluminum-polyethylene composites are also suitable. Thebacking should be substantially non-reactive with the ingredients of theadhesive coating. The presently preferred backing is low densitypolyethylene.

The pressure-sensitive adhesive coated sheet material of the inventioncan be made in the form of an article such as a tape, a patch, a sheet,a dressing or any other form known to those skilled in the art.

Preferably, an article in the form of a patch is made from an adhesivecoated sheet material of the invention and applied to the skin of amammal. The patch is replaced as necessary with a fresh patch tomaintain the particular desired therapeutic effect of the1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine.

The inherent viscosity values reported in the Examples below wereobtained by the conventional method used by those skilled in the art.The measurement of the viscosity of dilute solutions of the adhesive,when compared to controls run under the same conditions, clearlydemonstrates the relative molecular weights. It is the comparativevalues that are significant; absolute figures are not required. In theexamples, the inherent viscosity values were obtained using aCannon-Fenske #50 viscometer to measure the flow time of 10 ml of apolymer solution (0.2 g polymer/deciliter tetrahydrofuran, in a waterbath controlled at 25° C.). The examples and the controls were run underidentical conditions. The test procedure followed and the apparatus usedare explained in detail in the Textbook of Polymer Science, F. W.Billmeyer, Wiley-Interscience, 2nd Edition, 1971 under: Polymer chainsand their characterization, D. Solution Viscosity and Molecular Size, pp84-85, the disclosure and textbook of which is incorporated byreference.

As indicated herein above, and in accordance with the present invention,the present invention contemplates bioequivalent or interchangeablelower dosage strength imiquimod formulations. By way of an example,bioequivalent or interchangeable 3.75% lower dosage strength imiquimodtopical formulations, as contemplated by the present invention, includethose 3.75% imiquimod formulations that have comparable in-vivo serumprofiles, i.e., wherein the following in-vivo parameters are either thesame or may vary up to about ±25% or more (See also FIG. 54), when such3.75% formulations are topically administered daily to the sameindividuals in the same dosage regimen in accordance with the shortdurations of therapy, such as the two-cycle therapies, of the presentinvention:

(a) a Day 21 T_(max) of from about 4 hours to about 16 hours andpreferably a mean T_(max) of about 7.4 hours with a standard deviation(“SD”) of about 3.5, a median T_(max) of about 9 hours and a geometricmean T_(max) of about 6.6 hours and a coefficient of variation (“CV”) ofabout 48%;

(b) a Day 21 C_(max) of from about 0.07 to about 0.6 ng/ml andpreferably a mean C_(max) of about 0.3 ng/ml with a standard deviationof about 0.16, a median C_(max) of about 0.35 and a geometric meanC_(max) of about 0.27 ng/ml and a coefficient of variation of about 49%;

(c) a Day 21 T_(1/2) of from about 9.7 to about 84 hours and preferablya mean T_(1/2) of about 29.3 hours with a standard deviation of about17, a median T_(1/2) of about 25.6 hours and a geometric mean T_(1/2) ofabout 26 hours and a coefficient of variation of about 58%;

(d) a Day 21 AUC₀₋₂₄ of from about 1.1 to about 12 nghr/ml andpreferably a mean AUC₀₋₂₄ of about 6 nghr/ml with a standard deviationof about 3, a median AUC₀₋₂₄ of about 7 nghr/ml and a geometric meanAUC₀₋₂₄ of about 5 nghr/ml and a coefficient of variation of about 52%;

(e) a Day 21 λz of from about 0.008 hr⁻¹ to about 0.07 hr⁻¹ andpreferably a mean λz of about 0.03 hr⁻¹ with a standard deviation ofabout 0.01, a median λz of about 25.6 hr⁻¹ and a geometric mean λz ofabout 0.03 hr⁻¹ and a coefficient of variation of about 49%;

(f) a Day 21 C_(min) of from about 0.06 to about 0.4 and preferably amean C_(min) of about 0.20 with an SD of about 0.11, a median C_(min) ofabout 0.19 and a geometric mean C_(min) of about 0.17 and a coefficientof variation of about 55%;

(g) at Day 14/7 (a ratio of the trough concentration at Day 14 over thetrough concentration at Day 7), a trough concentration geometric meanratio of about 1.09 with a 90% confidence interval (“CI”) within a rangeof between about 0.8 and about 1.5;

(h) at Day 21/14 (a ratio of the trough concentration at Day 21 over thetrough concentration at Day 14), a trough concentration geometric meanratio of about 1.33 with a 90% confidence interval (“CI”) within a rangeof between about 0.9 and about 1.9;

(i) at Day 22/21 (a ratio of the trough concentration at Day 22 over thetrough concentration at Day 21) a trough concentration geometric meanratio of about 0.93 with a 90% confidence interval (“CI”) within a rangeof between about 0.6 and about 1.3;

(j) a mean peak imiquimod serum concentration of about 0.323 ng/ml atDay 21;

(k) a Day 21 RAUC of from about 1 to about 7 and preferably a mean RAUCof about 4 with a standard deviation of about 2, a median RAUC of about3.5 and a geometric mean RAUC of about 3.3 and a coefficient ofvariation of about 56%;

(l) a Day 21 RC_(max) of from about 0.5 to about 5 and preferably a meanRC_(max) of about 3 with a standard deviation of about 1.5, a medianRC_(max) of about 2.7 and a geometric mean RC_(max) of about 2.4 and acoefficient of variation of about 54%;

(m) a Day 21 Lλz_(eff) of from about 0.006 hr⁻¹ to about 0.08 hr⁻¹ andpreferably a mean Lλz_(eff) of about 0.02 hr⁻¹ with a standard deviationof about 0.02, a median Lλz_(eff) of about 0.01 hr⁻¹ and a geometricmean Lλz_(eff) of about 0.16 hr⁻¹ and a coefficient of variation ofabout 97%; and

(n) a Day 21 T^(1/2) _(eff) of from about 8 hr to about 110 hr andpreferably a mean T^(1/2) _(eff) of about 55 hr with a standarddeviation of about 36, a median T^(1/2) _(eff) of about 50 hr and ageometric mean T^(1/2) _(eff) of about 42 hr⁻¹ and a coefficient ofvariation of about 66%.

While the lower dosage strength imiquimod pharmaceutical formulations ofthe present invention can be formulated into any form known to the art,such as a cream, an ointment, a foam, a gel, a lotion or apressure-sensitive adhesive composition or patch, it should beunderstood that the creams, ointments, foams, gels and lotions may bepackaged into any suitable container, such as unit-dose sachets orpackets or multi-dose tubes or containers. A packaged amount of animiquimod pharmaceutical formulation contemplated by the presentinvention includes any suitable amount, such as about 250 mg to about500 mg or more, and preferably about 250 mg, about 300 mg, about 350 mg,about 400 mg, about 450 mg or about 500 mg unit-dose sachets or packets.

Examples of various embodiments of the present invention will now befurther illustrated with reference to the following examples. Thus, thefollowing examples are provided to illustrate the invention, but are notintended to be limiting thereof. Parts and percentages are by weightunless otherwise specified. Examples of creams, ointments and pressuresensitive adhesive compositions contemplated by the present inventionare described in U.S. Pat. No. 4,689,338 and U.S. Pat. No. 5,238,944,which are incorporated herein by reference in their entireties. Percentmodifications for, e.g., imiquimod and vehicle, to generate imiquimodformulations as described herein are likewise contemplated by thepresent invention. In addition, the formulations described and disclosedin U.S. Patent Publication No. 2007/0123558, Ser. No. 11/276,324, U.S.Patent Publication No. 2007/0264317, Serial No. 433,471, andUS2007/0900550, Publication No. WO2008098232 (A1), are also contemplatedby the present invention and are incorporated herein by reference intheir entireties.

Preparative Method 1 Laboratory Scale Preparation ofIsooctylacrylate/Acrylamide Copolymer

To a 114 gram narrow-mouth glass bottle were added: 18.6 g isooctylacrylate, 1.4 g acrylamide, 0.04 g benzoyl peroxide, 27.0 g ethylacetate and 3.0 g methanol. The solution was purged for thirty fiveseconds with nitrogen at a flow rate of one liter per minute. The bottlewas sealed and placed in a rotating water bath at 55° C. for twenty-fourhours to effect essentially complete polymerization. The polymer wasdiluted with ethyl acetate/methanol (90/10) to 23.2 percent solids andhad a measured inherent viscosity of 1.26 dl/g in ethyl acetate.

Preparative Method 2 Pilot Plant Scale Preparation ofIsooctylacrylate/Acrylamide Copolymer

155 kg isooctylacrylate, 11.6 kg acrylamide, 209.1 kg ethyl acetate and23.2 kg methanol were charged to a clean, dry reactor. Medium agitationwas applied. The batch was deoxygenated with nitrogen while heating toan induction temperature of 55° C. 114 g Lucidol™ 70 initiator(available from Pennwalt Corp.) mixed with 2.3 kg ethyl acetate wascharged to the reactor. The temperature was maintained at 55° C.throughout the reaction. After 5.5 hours reaction time, 114 g Lucidol™70 mixed with 2.3 kg ethyl acetate were charged to the reactor. After9.0 hours reaction time, an additional 114 g Lucidol™ 70 initiator mixedwith 2.3 kg ethyl acetate were charged to the reactor. The reaction wascontinued until the percent conversion was greater than 98 percent asmeasured by gas chromatographic evaluation of residual monomerconcentration. The resulting polymer solution was diluted to 25-28percent solids with ethyl acetate/methanol (90/10) and had a measuredBrookfield viscosity of 17,000-21,000 centipoises using spindle #4 at 12rpm. The polymer had a measured inherent viscosity of 1.3-1.4 dllg inethyl acetate.

The above-mentioned procedure was found to provide a pressure-sensitiveadhesive that is equivalent in the practice of the present invention toa pressure-sensitive adhesive prepared according to Preparative Method1.

A 25-30 percent solids solution of the isooctyl acrylate:acrylamide(93:7) adhesive copolymer in ethyl acetate/methanol (90:10) was coatedonto a two-sided release liner using a knife-coater and coating at 0.5mm in thickness. The adhesive-coated laminate was dried first at 82° C.for 3 minutes and then at 116° C. for 3 minutes. The dried adhesivecoating was then stripped off the release liner and placed in a glassbottle. The foregoing procedure results in a reduction of the amount ofany residual monomer in the adhesive copolymer.

Preparative Method 3 Preparation of Isooctyl Acrylate: Acrylamide: VinylAcetate (75:5:20) Copolymer

The procedure of Preparative Method 1 above acrylate, 8.0 g acrylamide,32.0 g vinyl acetate, 0.32 g benzoyl peroxide, 216.0 g ethyl acetate and24.0 g methyl alcohol. The resulting polymer was diluted with the ethylacetate/methyl alcohol mixture to 21.52% solids. The adhesive polymerhad a measured inherent viscosity of 1.40 dl/g in ethyl acetate at aconcentration of 0.15 g/dl. Its Brookfield viscosity was 2,300centipoise.

Preparative Method 4 Preparation of Isooctyl Acrylate Acrylamide: VinylAcetate (75:5:20) Copolymer

A master batch was prepared by combining 621.0 g of isooctyl acrylate,41.4 g of acrylamide, 165.6 g of vinyl acetate, 1.656 g of2,2′-azobis(2,4-dimethylpentanenitrile) (available from the DuPontCompany as Vazo.™.52), 884.52 g of ethyl acetate and 87.48 g ofmethanol. A 400 g portion of the resulting solution was placed in anamber quart bottle. The bottle was purged for two minutes with nitrogenat a flow rate of one liter per minute. The bottle was sealed and placedin a rotating water bath at 45° C. for twenty-four hours to effectessentially complete polymerization. The copolymer was diluted with 250g of ethyl acetate/methanol (90/10) to 26.05% solids and had a measuredinherent viscosity of 1.27 dl/g in ethyl acetate at a concentration of0.15 g/dl. Its Brookfield viscosity was 5580 centipoise.

Example 1

A cream according to the present invention is prepared from thefollowing ingredients:

% by Weight Amount Oil Phase 1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-1.0 40.0 g amine Isostearic acid 10.0 400.0 g  Benzyl alcohol 2.0 80.0 gCetyl alcohol 2.2 88.0 g Stearyl alcohol 3.1 124.0 g  Polysorbate 602.55 102.0 g  Sorbitan monostearate 0.45 18.0 g Aqueous Phase Glycerin2.0 80.0 g Methylparaben 0.2  8.0 g Propylparaben 0.02  0.8 g Purifiedwater 76.48 3059.2 g 

The materials listed above were combined according to the followingprocedure:

The glycerin, methylparaben, propylparaben and water were weighed into a4 liter glass beaker then heated on a hot plate with stiffing until theparabens isostearic acid and1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine were weighed into an 8liter stainless steel beaker and heated on a hot plate until the aminewas in solution (the temperature reached 69° C.). The benzyl alcohol,cetyl alcohol, stearyl alcohol, polysorbate 60 and sorbitan monostearatewere added to the isostearic acid solution and heated on a hot plateuntil all material was dissolved (the temperature reached 75° C.). Withboth phases at approximately the same temperature (65°-75° C.), thewater phase was added to the oil phase. The mixture was mixed with ahomogenizer for 13 minutes then put into a cool water bath and mixedwith a 3 inch propeller for 40 minutes (the temperature was 29° C.). Theresulting cream was placed in glass jars.

Examples 2-9

Using the general method of Example 1, the cream formulations shown inTables 1 and 2 are prepared.

TABLE 1 % by Weight Example 2 Example 3 Example 4 Example 5 Oil Phase1-isobutyl-1H-imidazo- 1.0 1.0 1.0 1.0 [4,5-c]quinolin-4-amineIsostearic acid 10.0 10.0 5.0 5.0 Benzyl alcohol 2.0 Cetyl alcohol 1.7Stearyl alcohol 2.3 Cetearyl alcohol 6.0 6.0 6.0 Polysorbate 60 2.552.55 2.55 2.55 Sorbitan monostearate 0.45 0.45 0.45 0.45 Brij ™ 30^(a)10.0 Aqueous Phase Glycerin 2.0 2.0 2.0 2.0 Methylparaben 0.2 0.2 0.20.2 Propylparaben 0.02 0.02 0.02 0.02 Purified water 77.78 77.78 82.7872.78 ^(a)Brij ™ 30 (polyoxyethylene(4) lauryl ether) is available fromICI Americas, Inc.

TABLE 2 % by Weight Example 6 Example 7 Example 8 Example 9 Oil Phase1-isobutyl-1H-imidazo- 1.0 1.0 1.0 1.0 [4,5-c]quinolin-4-amineIsostearic acid 10.0 25.0 10.0 6.0 Benzyl alcohol 2.0 2.0 Cetyl alcohol2.2 1.7 Stearyl alcohol 3.1 2.3 Cetearyl alcohol 6.0 6.0 Polysorbate 602.55 3.4 2.55 2.55 Sorbitan monostearate 0.45 0.6 0.45 0.45 Brij ™30^(a) 10.0 Aqueous Phase Glycerin 2.0 2.0 2.0 2.0 Methylparaben 0.2 0.20.2 0.2 Propylparaben 0.02 0.02 0.02 0.02 Purified water 67.78 60.4879.78 79.78 ^(a)Brij ™ 30 (polyoxyethylene(4) lauryl ether) is availablefrom ICI Americas, Inc.

Example 10

A cream according to the present invention is prepared from thefollowing ingredients in the following Table 3:

TABLE 3 % by Weight Amount Oil Phase 1-isobutyl-1H-imidazo[4,5- 1.0 3.00g c]quinolin-4-amine Isostearic acid 5.0 15.0 g White petrolatum 15.045.0 g Light mineral oil 12.8 38.4 g Aluminum stearate 8.0 24.0 g Cetylalcohol 4.0 12.0 g Witconol ™ 14^(a) 3.0 9.00 g Acetylated lanolin 1.0 3.0 g Propylparaben 0.063 0.19 g Aqueous Phase Veegum ™ K^(b) 1.0  3.0g Methylparaben 0.12 0.36 g Purified water 49.017 147.05 g ^(a)Witconol ™ 14 (polyglyceryl4 oleate) is available from WitcoChemical Corp. Organics Division ^(b)Veegum ™ K (colloidal magnesiumaluminum silicate) is available from R. T. Vanderbilt Company Inc.

The materials listed above were combined according to the followingprocedure:

The 1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine and the isostearic acidwere weighed into a glass jar and heated with occasional stirring untilthe amine was dissolved (the temperature reached 68° C.). To thissolution was added, the petrolatum, mineral oil, aluminum stearate,cetyl alcohol, Witconol™ 14, acetylated lanoline and propylparaben. Themixture was heated to 75° C. In a separate beaker, the methylparaben andwater were combined and heated until the paraben dissolved (thetemperature reached 61° C.). The VeeGum™ K was added to the aqueoussolution and heated at 75° C. for 30 minutes while mixing with ahomogenizer. With both phases at 75° C., the aqueous phase was slowlyadded to the oil phase while mixing with a homogenizer. Mixing wascontinued for 30 minutes while maintaining a temperature to about 80° C.The jar was then capped and the formulation was allowed to cool.

Example 11

An ointment according to the present invention is prepared from theingredients in the following Table 4:

TABLE 4 % by Weight Amount 1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine1.0 0.20 g Isostearic acid 5.0 1.00 g Mineral oil 12.8 2.56 g Whitepetrolatum 65.2 13.04 g  Cetyl alcohol 4.0 0.80 g Acetylated lanolin 1.00.20 g Witconol ™ 143.0 0.60 g Aluminum stearate 8.0 1.60 g

The materials listed above are combined according to the followingprocedure:

The 1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine and the isostearic acidwere placed in a glass jar and heated with stirring until the amine wasdissolved. The remaining ingredients were added and the resultingmixture was heated to 65° C. and then mixed while being allowed to coolto room temperature.

Example 12

Using the general procedure of Example 11 an ointment containing theingredients in the following Table 5 is prepared.

TABLE 5 % by Weight Amount 1-Tsobutyl-1H-imidazo[4,5-c]quinolin-4-amine1.0 0.20 g Isostearic acid 6.0 1.20 g Polyethylene Glycol 400 55.8 11.16g  Polyethylene Glycol 3350 32.6 6.52 g Stearyl alcohol 4.6 0.92 g

Examples 13-15

Creams of the present invention are prepared using the ingredients shownin Table 6. The Example 1 except that benzyl alcohol was used with theisostearic acid to dissolve the1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine.

TABLE 6 Example 13 Example 14 Example 15 Amount % Amount % Amount % byby Weight by Weight Weight Oil Phase 1-isobutyl-1H-imidazo[4,5- 50 5.04.85 c]quinolin-4-amine Isostearic acid 25.0 25.0 24.3 Benzyl alcohol2.0 2.0 1.94 Cetyl alcohol 2.2 2.2 1.16 Stearyl alcohol 3.1 3.1 1.75Petrolatum 3.0 2.91 Polysorbate 60 3.4 3.4 4.13 Sorbitan monostearate0.6 0.6 0.73 Stearic acid 9.71 Aqueous Phase Glycerin 2.0 2.0 1.94Methylparaben 0.2 0.2 0.19 Propylparaben 0.02 0.02 0.02

Example 16

A cream according to the present invention is prepared from theingredients in the following Table 7:

TABLE 7 % by Weight % by Weight Amount Amount Oil Phase1-isobutyl-1H-imidazo[4,5-c]quinolin-4- 4.0 0.80 g amine Isostearic acid20.0 4.00 g Benzyl alcohol 2.0 0.40 g Cetyl alcohol 2.2 0.49 g Stearylalcohol 3.1 0.62 g Polysorbate 60 3.4 0.68 g Sorbitan monostearate 0.60.12 g Aqueous Phase 1-isobutyl-1H-imidazo [4,5-c]quinolin-4- 1.0  0.2 gamine Glycerin 2.0  0.4 g 85% Lactic acid 1.0 0.22 g Methylparaben 0.20.04 g Propylparaben 0.02 0.004 g  Purified water 60.48 12.0 g

The materials listed above are combined according to the followingprocedure:

The isostearic acid and 0.8 g of1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine or1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine were combined in aglass jar and heated with stirring until the amine had dissolved. Theremaining oil phase ingredients were added to this solution and themixture was heated to about 70° C. The aqueous phase ingredients wereweighed into a separate beaker and heated with stirring until the amineand the parabens had dissolved. With both phases at about 70° C., thewater phase was added to the oil phase and mixed with a propeller untilthe mixture cooled to room temperature.

Example 17

A mixture of 5.9415 g of the 93:7 isooctyl acrylate:acrylamide adhesivecopolymer prepared in PREPARATIVE METHOD 2 above, 1.5126 g isostearicacid, 2.0075 g ethyl oleate, 0.3021 g glyceryl monolaurate, 0.29361-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine (micronized) and 23.7 g of90:10 ethyl acetate: methanol was placed in a small glass jar. The jarwas placed on a horizontal shaker and shaken at room temperature forabout 13 hours. The formulation was coated at a thickness of 20 milsonto a 5 mil Daubert 164Z liner. The laminate was oven dried for 3minutes at 105° F., for 2 minutes at 185° F., and for 2 minutes at 210°F. The resulting adhesive coating contained 59.1 percent 93:7 isooctylacrylate:acylamide adhesive copolymer, 15.0 percent isostearic acid,20.0 percent ethyl oleate, 3.0 percent glyceryl monolaurate and 2.9percent 1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine. The material wasthen laminated with 3 mil low density polyethylene backing and die cutinto 2.056 cm.sup.2 patches.

Examples 18-20 Pressure-Sensitive Adhesive Coated Sheet MaterialsPrepared Using Unmicronized 1-isobutyl-1H-imidazo[4,5-c]quinolin-4-amine

Using the general method of Example 17 the formulations shown below areprepared. 1-Isobutyl-1H-imidazo[4,5-c]quinolin-4-amine or1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine that had beenground with a mortar and pestle was used. The adhesive was the 93:7isooctyl acrylate: acrylamide copolymer prepared in Preparative Method 1above. The solvent was 90:10 ethyl acetate:methanol. All formulations inthe following Table 8 were mixed at room temperature.

TABLE 8 Example 18 Example 19 Example 20 1-isobutyl-1H-imidazo[4,5- 5.03.0 3.0 c]quinolin-4-amine Ethyl oleate 5.1 5.0 8.0 Isostearic acid 10.010.0 6.0 Oleic acid 20.0 20.0 13.0 Glyceryl monolaurate 1.5 1.5 1.5N,N-dimethyldodecylamine- 1.0 1.1 3.0 N-oxide Adhesive 57.4 59.3 65.4

Example 21

A formulation with the same components in the same proportions asExample 18 is prepared using a different method. The1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine or1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine was combined withthe oleic and isostearic acids and shaken at 40° C. until there wascomplete dissolution of the1-isobutyl-1H-imidazo-[4,5-c]quinolin-4-amine or 1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine. The remaining ingredients wereadded and shaken a 40° C. for 72 hours. Patches measuring 2.056 cm.sup.2were prepared by the general method of Example 17.

Example 22

A mixture of 2.4734 g 1-isobutyl-1H-imidazo[4,5-c]-quinolin-4-amine or1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine, 3.3315 gisostearic acid and 6.6763 g oleic acid is prepared. To 1.8738 g of theabove mixture was added 2.8750 g of the 93:7 isooctyl acrylate:acryamideadhesive copolymer prepared in Preparative Method 2 above, 0.2548 g ofethyl oleate, 0.0510 g N,N-dimethyldodecylamine-N-oxide, 0.0820 gglyceryl monolaurate (from Lauricidin, Inc.) and 14.0457 g of 90:10ethyl acetate/methanol. The above was shaken for 30 hours at roomtemperature on a horizontal shaker. Transdermal patches were thenprepared generally according to the procedures of Example 17.

Example 23 Topical Imiquimod Pharmaceutical Cream Formulations

Creams are prepared in accordance with the present invention using theingredients shown in this Example 23.

The materials listed below in this Example 23 are combined according tothe following procedure to make cream formulations in the followingTable 9 of this Example 23:

TABLE 9 Lower Dosage Strength Imiquimod Formulations Excipients % w/w %w/w % w/w % w/w % w/w % w/w Formulation 1 2 3 4 5 6 Fatty acid* 15.0015.00 15.00 20.00 15.00 20.00 Cetyl alcohol 2.20 2.20 2.20 2.20 2.202.20 Stearyl alcohol 3.10 3.10 3.10 3.10 3.10 3.10 White 1.00 3.00 2.003.00 6.00 3.00 petrolatum Polysorbate 60 3.40 3.40 3.40 3.40 3.00 3.00Sorbitan 0.60 0.60 0.60 0.60 1.00 1.00 Monostearate Glycerin 2.00 2.005.00 2.00 5.00 3.00 Xanthan gum 0.50 0.50 0.50 0.50 0.75 0.75 Purifiedwater 68.98 66.98 64.98 61.98 60.73 60.73 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 1.00 1.00 1.00 1.00 1.00 1.00Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 7 8 9 10 11 12 Fatty acid* 15.00 15.0015.00 25.00 18.0 25.00 Cetyl alcohol 2.20 2.20 2.20 2.20 2.20 2.70Stearyl alcohol 3.10 3.10 3.10 3.10 3.10 3.80 White 3.00 6.00 6.00 3.005.00 3.00 petrolatum Polysorbate 60 3.40 3.40 3.00 3.40 3.00 3.40Sorbitan 0.60 0.60 1.00 0.50 1.00 0.60 Monostearate Glycerin 2.00 5.005.00 2.00 5.00 2.00 Xanthan gum 0.50 0.50 0.50 0.50 0.50 0.50 Purifiedwater 66.98 60.98 60.98 57.08 58.98 55.78 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 1.00 1.00 1.00 1.00 1.00 1.00Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 13 14 15 16 17 18 Fatty acid* 25.0015.00 20.00 20.00 20.00 20.00 Cetyl alcohol 2.20 2.00 2.20 2.20 2.202.20 Stearyl alcohol 3.10 2.00 3.10 3.10 3.10 3.10 White 3.00 3.40 5.003.00 5.00 3.00 petrolatum Polysorbate 60 3.40 3.80 3.40 3.40 3.40 3.40Sorbitan 0.60 0.2 0.60 0.60 0.60 0.60 Monostearate Glycerin 2.00 3.002.00 5.00 5.00 2.00 Xanthan gum 1.00 0.30 0.50 0.50 0.50 0.50 Purifiedwater 56.48 67.08 59.98 58.98 56.98 61.98 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 1.00 1.00 1.00 1.00 1.00 1.00Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 19 20 21 22 23 24 Fatty acid* 15.0015.00 15.00 20.00 15.00 20.00 Cetyl alcohol 2.20 2.20 2.20 2.20 2.202.20 Stearyl alcohol 3.10 3.10 3.10 3.10 3.10 3.10 White 1.00 3.00 2.003.00 6.00 3.00 petrolatum Polysorbate 60 3.40 3.40 3.40 3.40 3.00 3.00Sorbitan 0.60 0.60 0.60 0.60 1.00 1.00 Monostearate Glycerin 2.00 2.005.00 2.00 5.00 3.00 Xanthan gum 0.50 0.50 0.50 0.50 0.75 0.75 Purifiedwater 68.73 66.73 64.73 61.73 60.48 60.48 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 1.25 1.25 1.25 1.25 1.25 1.25Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 25 26 27 28 29 30 Fatty acid* 15.0015.00 15.00 25.00 18.0 25.00 Cetyl alcohol 2.20 2.20 2.20 2.20 2.20 2.70Stearyl alcohol 3.10 3.10 3.10 3.10 3.10 3.80 White 3.00 6.00 6.00 3.005.00 3.00 petrolatum Polysorbate 60 3.40 3.40 3.00 3.40 3.00 3.40Sorbitan 0.60 0.60 1.00 0.50 1.00 0.60 Monostearate Glycerin 2.00 5.005.00 2.00 5.00 2.00 Xanthan gum 0.50 0.50 0.50 0.50 0.50 0.50 Purifiedwater 66.73 60.73 60.73 56.83 58.73 55.53 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 1.25 1.25 1.25 1.25 1.25 1.25Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 31 32 33 34 35 36 Fatty acid* 25.0015.00 20.00 20.00 20.00 20.00 Cetyl alcohol 2.20 2.00 2.20 2.20 2.202.20 Stearyl alcohol 3.10 2.00 3.10 3.10 3.10 3.10 White 3.00 3.40 5.003.00 5.00 3.00 petrolatum Polysorbate 60 3.40 3.80 3.40 3.40 3.40 3.40Sorbitan 0.60 0.2 0.60 0.60 0.60 0.60 Monostearate Glycerin 2.00 3.002.00 5.00 5.00 2.00 Xanthan gum 1.00 0.30 0.50 0.50 0.50 0.50 Purifiedwater 56.23 66.83 59.73 58.73 56.73 61.73 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 1.25 1.25 1.25 1.25 1.25 1.25Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 37 38 39 40 41 42 Fatty acid* 15.0015.00 15.00 20.00 15.00 20.00 Cetyl alcohol 2.20 2.20 2.20 2.20 2.202.20 Stearyl alcohol 3.10 3.10 3.10 3.10 3.10 3.10 White 1.00 3.00 2.003.00 6.00 3.00 petrolatum Polysorbate 60 3.40 3.40 3.40 3.40 3.00 3.00Sorbitan 0.60 0.60 0.60 0.60 1.00 1.00 Monostearate Glycerin 2.00 2.005.00 2.00 5.00 3.00 Xanthan gum 0.50 0.50 0.50 0.50 0.75 0.75 Purifiedwater 68.48 66.48 64.48 61.48 60.23 60.23 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 1.50 1.50 1.50 1.50 1.50 1.50Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 43 44 45 46 47 48 Fatty acid* 15.0015.00 15.00 25.00 18.0 25.00 Cetyl alcohol 2.20 2.20 2.20 2.20 2.20 2.70Stearyl alcohol 3.10 3.10 3.10 3.10 3.10 3.80 White 3.00 6.00 6.00 3.005.00 3.00 petrolatum Polysorbate 60 3.40 3.40 3.00 3.40 3.00 3.40Sorbitan 0.60 0.60 1.00 0.50 1.00 0.60 Monostearate Glycerin 2.00 5.005.00 2.00 5.00 2.00 Xanthan gum 0.50 0.50 0.50 0.50 0.50 0.50 Purifiedwater 66.48 60.48 60.48 56.58 58.48 55.28 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 1.50 1.50 1.50 1.50 1.50 1.50Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 49 50 51 52 53 54 Fatty acid* 25.0015.00 20.00 20.00 20.00 20.00 Cetyl alcohol 2.20 2.00 2.20 2.20 2.202.20 Stearyl alcohol 3.10 2.00 3.10 3.10 3.10 3.10 White 3.00 3.40 5.003.00 5.00 3.00 petrolatum Polysorbate 60 3.40 3.80 3.40 3.40 3.40 3.40Sorbitan 0.60 0.2 0.60 0.60 0.60 0.60 Monostearate Glycerin 2.00 3.002.00 5.00 5.00 2.00 Xanthan gum 1.00 0.30 0.50 0.50 0.50 0.50 Purifiedwater 55.98 66.58 59.48 58.48 56.48 61.48 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 1.50 1.50 1.50 1.50 1.50 1.50Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 55 56 57 58 59 60 Fatty acid* 15.0015.00 15.00 20.00 15.00 20.00 Cetyl alcohol 2.20 2.20 2.20 2.20 2.202.20 Stearyl alcohol 3.10 3.10 3.10 3.10 3.10 3.10 White 1.00 3.00 2.003.00 6.00 3.00 petrolatum Polysorbate 60 3.40 3.40 3.40 3.40 3.00 3.00Sorbitan 0.60 0.60 0.60 0.60 1.00 1.00 Monostearate Glycerin 2.00 2.005.00 2.00 5.00 3.00 Xanthan gum 0.50 0.50 0.50 0.50 0.75 0.75 Purifiedwater 68.23 66.23 64.23 61.23 59.98 59.98 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 1.75 1.75 1.75 1.75 1.75 1.75Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 61 62 63 64 65 66 Fatty acid* 15.0015.00 15.00 25.00 18.0 25.00 Cetyl alcohol 2.20 2.20 2.20 2.20 2.20 2.70Stearyl alcohol 3.10 3.10 3.10 3.10 3.10 3.80 White 3.00 6.00 6.00 3.005.00 3.00 petrolatum Polysorbate 60 3.40 3.40 3.00 3.40 3.00 3.40Sorbitan 0.60 0.60 1.00 0.50 1.00 0.60 Monostearate Glycerin 2.00 5.005.00 2.00 5.00 2.00 Xanthan gum 0.50 0.50 0.50 0.50 0.50 0.50 Purifiedwater 66.23 60.23 60.23 56.33 58.23 55.03 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 1.75 1.75 1.75 1.75 1.75 1.75Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 67 68 69 70 71 72 Fatty acid* 25.0015.00 20.00 20.00 20.00 20.00 Cetyl alcohol 2.20 2.00 2.20 2.20 2.202.20 Stearyl alcohol 3.10 2.00 3.10 3.10 3.10 3.10 White 3.00 3.40 5.003.00 5.00 3.00 petrolatum Polysorbate 60 3.40 3.80 3.40 3.40 3.40 3.40Sorbitan 0.60 0.2 0.60 0.60 0.60 0.60 Monostearate Glycerin 2.00 3.002.00 5.00 5.00 2.00 Xanthan gum 1.00 0.30 0.50 0.50 0.50 0.50 Purifiedwater 55.73 66.33 59.23 58.23 56.23 61.23 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 1.75 1.75 1.75 1.75 1.75 1.75Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 73 74 75 76 77 78 Fatty acid* 10.0012.50 25.00 10.00 15.00 20.00 Cetyl alcohol 2.20 2.20 2.70 4.00 4.002.20 Stearyl alcohol 3.10 3.10 3.80 2.00 2.00 3.10 White 5.00 5.00 3.003.40 2.80 3.00 petrolatum Polysorbate 60 3.40 3.40 3.40 3.80 3.00 3.00Sorbitan 0.60 0.60 0.60 1.00 1.00 1.00 Monostearate Glycerin 5.00 5.002.00 1.00 3.00 3.00 Xanthan gum 0.50 0.50 0.50 0.30 0.70 0.75 Purifiedwater 65.98 63.48 54.78 70.28 64.28 59.73 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 2.00 2.00 2.00 2.00 2.00 2.00Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 79 80 81 82 83 84 Fatty acid* 10.0012.50 25.00 10.00 15.00 25.00 Cetyl alcohol 2.20 2.20 2.70 4.00 4.002.70 Stearyl alcohol 3.10 3.10 3.80 2.00 2.00 3.80 White 5.00 5.00 3.003.40 2.80 3.00 petrolatum Polysorbate 60 3.40 3.40 3.40 3.80 3.00 3.40Sorbitan 0.60 0.60 0.60 1.00 1.00 0.60 Monostearate Glycerin 5.00 5.002.00 1.00 3.00 2.00 Xanthan gum 0.50 0.50 0.50 0.30 0.70 0.50 Purifiedwater 65.98 63.48 54.78 70.28 64.28 54.78 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 2.00 2.00 2.00 2.00 2.00 2.00Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 85 86 87 88 89 90 Fatty acid* 25.0015.00 20.00 20.00 20.00 20.00 Cetyl alcohol 2.20 2.00 2.20 2.20 2.202.20 Stearyl alcohol 3.10 2.00 3.10 3.10 3.10 3.10 White 3.00 3.40 5.003.00 5.00 3.00 petrolatum Polysorbate 60 3.40 3.80 3.40 3.40 3.40 3.40Sorbitan 0.60 0.2 0.60 0.60 0.60 0.60 Monostearate Glycerin 2.00 3.002.00 5.00 5.00 2.00 Xanthan gum 1.00 0.30 0.50 0.50 0.50 0.50 Purifiedwater 55.48 66.08 58.98 57.98 55.98 60.98 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 2.00 2.00 2.00 2.00 2.00 2.00Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 91 92 93 94 95 96 Fatty acid* 15.0012.50 25.00 15.00 10.00 20.00 Cetyl alcohol 2.20 2.20 2.20 2.00 2.002.20 Stearyl alcohol 3.10 3.10 3.10 2.00 2.40 3.10 White 6.00 5.00 3.003.40 2.80 3.00 petrolatum Polysorbate 60 3.00 3.00 3.40 3.80 3.80 3.00Sorbitan 1.00 1.00 0.60 0.20 1.00 1.00 Monostearate Glycerin 5.00 5.002.00 3.00 3.00 3.00 Xanthan gum 1.00 0.50 1.00 0.30 0.30 0.75 Purifiedwater 60.23 63.23 55.23 66.83 70.23 59.48 Benzyl alcohol 1.00 2.00 2.001.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 2.25 2.25 2.25 2.25 2.25 2.25Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 97 98 99 100 101 102 Fatty acid* 15.0012.50 25.00 15.00 10.00 25.00 Cetyl alcohol 2.20 2.20 2.20 2.00 2.002.70 Stearyl alcohol 3.10 3.10 3.10 2.00 2.40 3.80 White 6.00 5.00 3.003.40 2.80 3.00 petrolatum Polysorbate 60 3.00 3.00 3.40 3.80 3.80 3.40Sorbitan 1.00 1.00 0.60 0.20 1.00 0.60 Monostearate Glycerin 5.00 5.002.00 3.00 3.00 2.00 Xanthan gum 1.00 0.50 1.00 0.30 0.30 0.50 Purifiedwater 60.23 63.23 55.23 66.83 70.23 54.53 Benzyl alcohol 1.00 2.00 2.001.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 2.25 2.25 2.25 2.25 2.25 2.25Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 103 104 105 106 107 108 Fatty acid*25.00 15.00 20.00 20.00 20.00 20.00 Cetyl alcohol 2.20 2.00 2.20 2.202.20 2.20 Stearyl alcohol 3.10 2.00 3.10 3.10 3.10 3.10 White 3.00 3.405.00 3.00 5.00 3.00 petrolatum Polysorbate 60 3.40 3.80 3.40 3.40 3.403.40 Sorbitan 0.60 0.2 0.60 0.60 0.60 0.60 Monostearate Glycerin 2.003.00 2.00 5.00 5.00 2.00 Xanthan gum 1.00 0.30 0.50 0.50 0.50 0.50Purified water 55.23 65.83 58.73 57.73 55.73 60.73 Benzyl alcohol 2.002.00 2.00 2.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20Propylparaben 0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 2.25 2.25 2.252.25 2.25 2.25 Total 100.00 100.00 100.00 100.00 100.00 100.00Excipients % w/w % w/w % w/w % w/w % w/w % w/w Formulation 109 110 111112 113 114 Fatty acid* 15.00 15.00 15.00 20.00 15.00 20.00 Cetylalcohol 2.20 2.20 2.20 2.20 2.20 2.20 Stearyl alcohol 3.10 3.10 3.103.10 3.10 3.10 White 2.50 3.00 2.00 3.00 6.00 3.00 petrolatumPolysorbate 60 3.40 3.40 3.40 3.40 3.00 3.00 Sorbitan 0.60 0.60 0.600.60 1.00 1.00 Monostearate Glycerin 2.00 2.00 5.00 2.00 5.00 3.00Xanthan gum 0.50 0.50 0.50 0.50 0.75 0.75 Purified water 65.98 65.4863.48 60.48 59.23 59.23 Benzyl alcohol 2.00 2.00 2.00 2.00 2.00 2.00Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben 0.02 0.02 0.020.02 0.02 0.02 Imiquimod 2.50 2.50 2.50 2.50 2.50 2.50 Total 100.00100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w % w/w % w/w %w/w % w/w Formulation 115 116 117 118 119 120 Fatty acid* 15.00 15.0015.00 25.00 18.0 25.00 Cetyl alcohol 2.20 2.20 2.20 2.20 2.20 2.70Stearyl alcohol 3.10 3.10 3.10 3.10 3.10 3.80 White 3.00 6.00 6.00 3.005.00 3.00 petrolatum Polysorbate 60 3.40 3.40 3.00 3.40 3.00 3.40Sorbitan 0.60 0.60 1.00 0.50 1.00 0.60 Monostearate Glycerin 2.00 5.005.00 2.00 5.00 2.00 Xanthan gum 0.50 0.50 0.50 0.50 0.50 0.50 Purifiedwater 65.48 59.48 59.48 55.58 57.48 54.28 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 2.50 2.50 2.50 2.50 2.50 2.50Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 121 122 123 124 125 126 Fatty acid*25.00 15.00 20.00 20.00 20.00 20.00 Cetyl alcohol 2.20 2.00 2.20 2.202.20 2.20 Stearyl alcohol 3.10 2.00 3.10 3.10 3.10 3.10 White 3.00 3.405.00 3.00 5.00 3.00 petrolatum Polysorbate 60 3.40 3.80 3.40 3.40 3.403.40 Sorbitan 0.60 0.2 0.60 0.60 0.60 0.60 Monostearate Glycerin 2.003.00 2.00 5.00 5.00 2.00 Xanthan gum 1.00 0.30 0.50 0.50 0.50 0.50Purified water 54.98 65.58 58.48 57.48 55.48 60.48 Benzyl alcohol 2.002.00 2.00 2.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20Propylparaben 0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 2.50 2.50 2.502.50 2.50 2.50 Total 100.00 100.00 100.00 100.00 100.00 100.00Excipients % w/w % w/w % w/w % w/w % w/w % w/w Formulation 127 128 129130 131 132 Fatty acid* 15.00 18.00 15.00 20.00 12.50 20.00 Cetylalcohol 2.00 2.00 2.00 2.00 2.20 2.20 Stearyl alcohol 2.00 2.00 2.402.40 3.10 3.10 White 3.40 2.80 3.40 2.80 5.00 3.00 petrolatumPolysorbate 60 3.00 3.80 3.00 3.00 3.40 3.00 Sorbitan 1.00 1.00 0.200.20 0.60 1.00 Monostearate Glycerin 3.00 2.00 1.00 3.00 6.00 3.00Xanthan gum 0.30 0.70 0.70 0.30 0.50 0.75 Purified water 65.08 62.4867.08 61.08 61.48 58.73 Benzyl alcohol 2.00 2.00 2.00 2.00 2.00 2.00Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben 0.02 0.02 0.020.02 0.02 0.02 Imiquimod 3.00 3.00 3.00 3.00 3.00 3.00 Total 100.00100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w % w/w % w/w %w/w % w/w Formulation 133 134 135 136 137 138 Fatty acid* 15.00 18.0015.00 20.00 12.50 25.00 Cetyl alcohol 2.00 2.00 2.00 2.00 2.20 2.70Stearyl alcohol 2.00 2.00 2.40 2.40 3.10 3.80 White 3.40 2.80 3.40 2.805.00 3.00 petrolatum Polysorbate 60 3.00 3.80 3.00 3.00 3.40 3.40Sorbitan 1.00 1.00 0.20 0.20 0.60 0.60 Monostearate Glycerin 3.00 2.001.00 3.00 6.00 2.00 Xanthan gum 0.30 0.70 0.70 0.30 0.50 0.50 Purifiedwater 65.08 62.48 67.08 61.08 61.48 53.78 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 3.00 3.00 3.00 3.00 3.00 3.00Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 139 140 141 142 143 144 Fatty acid*25.00 15.00 20.00 20.00 20.00 20.00 Cetyl alcohol 2.20 2.00 2.20 2.202.20 2.20 Stearyl alcohol 3.10 2.00 3.10 3.10 3.10 3.10 White 3.00 3.405.00 3.00 5.00 3.00 petrolatum Polysorbate 60 3.40 3.80 3.40 3.40 3.403.40 Sorbitan 0.60 0.2 0.60 0.60 0.60 0.60 Monostearate Glycerin 2.003.00 2.00 5.00 5.00 2.00 Xanthan gum 1.00 0.30 0.50 0.50 0.50 0.50Purified water 54.48 65.08 57.98 56.98 54.98 59.98 Benzyl alcohol 2.002.00 2.00 2.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20Propylparaben 0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 3.00 3.00 3.003.00 3.00 3.00 Total 100.00 100.00 100.00 100.00 100.00 100.00Excipients % w/w % w/w % w/w % w/w % w/w % w/w Formulation 145 146 147148 149 150 Fatty acid* 15.00 20.00 15.00 20.00 10.00 20.00 Cetylalcohol 2.00 2.00 4.00 4.00 2.20 2.20 Stearyl alcohol 2.00 2.40 2.402.40 3.10 3.10 White 3.40 2.80 2.50 3.40 5.00 3.00 petrolatumPolysorbate 60 3.00 3.00 3.00 3.80 3.40 3.00 Sorbitan 1.00 0.20 1.001.00 0.60 1.00 Monostearate Glycerin 3.00 3.00 1.00 3.00 5.00 3.00Xanthan gum 0.30 0.30 0.30 0.70 0.50 0.75 Purified water 64.83 60.8365.33 57.23 64.73 58.48 Benzyl alcohol 2.00 2.00 2.00 1.00 2.00 2.00Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben 0.02 0.02 0.020.02 0.02 0.02 Imiquimod 3.25 3.25 3.25 3.25 3.25 3.25 Total 100.00100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w % w/w % w/w %w/w % w/w Formulation 151 152 153 154 155 156 Fatty acid* 15.00 20.0015.00 20.00 10.00 25.00 Cetyl alcohol 2.00 2.00 4.00 4.00 2.20 2.70Stearyl alcohol 2.00 2.40 2.40 2.40 3.10 3.80 White 3.40 2.80 2.50 3.405.00 3.00 petrolatum Polysorbate 60 3.00 3.00 3.00 3.80 3.40 3.40Sorbitan 1.00 0.20 1.00 1.00 0.60 0.60 Monostearate Glycerin 3.00 3.001.00 3.00 5.00 2.00 Xanthan gum 0.30 0.30 0.30 0.70 0.50 0.50 Purifiedwater 64.83 60.83 65.33 57.23 64.73 53.53 Benzyl alcohol 2.00 2.00 2.001.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 3.25 3.25 3.25 3.25 3.25 3.25Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 157 158 159 160 161 162 Fatty acid*25.00 15.00 20.00 20.00 20.00 20.00 Cetyl alcohol 2.20 2.00 2.20 2.202.20 2.20 Stearyl alcohol 3.10 2.00 3.10 3.10 3.10 3.10 White 3.00 3.405.00 3.00 5.00 3.00 petrolatum Polysorbate 60 3.40 3.80 3.40 3.40 3.403.40 Sorbitan 0.60 0.2 0.60 0.60 0.60 0.60 Monostearate Glycerin 2.003.00 2.00 5.00 5.00 2.00 Xanthan gum 1.00 0.30 0.50 0.50 0.50 0.50Purified water 54.23 64.83 59.98 56.73 54.73 59.73 Benzyl alcohol 2.002.00 2.00 2.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20Propylparaben 0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 3.25 3.25 3.253.25 3.25 3.25 Total 100.00 100.00 100.00 100.00 100.00 100.00Excipients % w/w % w/w % w/w % w/w % w/w % w/w Formulation 163 164 165166 167 168 Fatty acid* 15.00 10.00 12.50 19.00 20.00 20.00 Cetylalcohol 2.00 2.20 2.20 2.20 2.20 2.20 Stearyl alcohol 2.40 3.10 3.103.10 3.10 3.10 White 3.40 5.00 5.00 3.00 3.00 3.00 petrolatumPolysorbate 60 3.00 3.40 4.00 3.40 3.40 3.00 Sorbitan 0.20 0.60 0.600.60 0.60 1.00 Monostearate Glycerin 1.00 4.00 5.00 2.00 6.00 3.00Xanthan gum 0.70 0.50 0.50 0.50 0.50 0.75 Purified water 66.58 65.4861.38 60.48 56.48 58.23 Benzyl alcohol 2.00 2.00 2.00 2.00 1.00 2.00Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben 0.02 0.02 0.020.02 0.02 0.02 Imiquimod 3.50 3.50 3.50 3.50 3.50 3.50 Total 100.00100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w % w/w % w/w %w/w % w/w Formulation 169 170 171 172 173 174 Fatty acid* 15.00 10.0012.50 19.00 20.00 25.00 Cetyl alcohol 2.00 2.20 2.20 2.20 2.20 2.70Stearyl alcohol 2.40 3.10 3.10 3.10 3.10 3.80 White 3.40 5.00 5.00 3.003.00 3.00 petrolatum Polysorbate 60 3.00 3.40 4.00 3.40 3.40 3.40Sorbitan 0.20 0.60 0.60 0.60 0.60 0.60 Monostearate Glycerin 1.00 4.005.00 2.00 6.00 2.00 Xanthan gum 0.70 0.50 0.50 0.50 0.50 0.50 Purifiedwater 66.58 65.48 61.38 60.48 56.48 53.28 Benzyl alcohol 2.00 2.00 2.002.00 1.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 3.50 3.50 3.50 3.50 3.50 3.50Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 175 176 177 178 179 180 Fatty acid*25.00 15.00 20.00 20.00 20.00 20.00 Cetyl alcohol 2.20 2.00 2.20 2.202.20 2.20 Stearyl alcohol 3.10 2.00 3.10 3.10 3.10 3.10 White 3.00 3.405.00 3.00 5.00 3.00 petrolatum Polysorbate 60 3.40 3.80 3.40 3.40 3.403.40 Sorbitan 0.60 0.2 0.60 0.60 0.60 0.60 Monostearate Glycerin 2.003.00 2.00 5.00 5.00 2.00 Xanthan gum 1.00 0.30 0.50 0.50 0.50 0.50Purified water 53.98 64.58 57.48 56.48 54.48 59.48 Benzyl alcohol 2.002.00 2.00 2.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20Propylparaben 0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 3.50 3.50 3.503.50 3.50 3.50 Total 100.00 100.00 100.00 100.00 100.00 100.00Excipients % w/w % w/w % w/w % w/w % w/w % w/w Formulation 181 182 183184 185 186 Fatty acid* 20.00 20.00 25.00 18.75 20.00 21.25 Cetylalcohol 4.00 2.20 2.20 2.20 2.20 2.20 Stearyl alcohol 2.40 3.10 3.103.10 3.10 3.10 White 2.80 3.00 3.00 5.00 5.00 3.75 petrolatumPolysorbate 60 3.00 3.40 3.40 3.00 3.40 3.40 Sorbitan 1.00 0.60 0.601.00 0.60 0.60 Monostearate Glycerin 1.00 2.00 2.00 5.00 5.00 5.00Xanthan gum 0.30 0.50 0.50 0.50 0.50 0.50 Purified water 64.53 59.2354.23 55.48 54.23 54.23 Benzyl alcohol 2.00 2.00 2.00 2.00 2.00 2.00Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben 0.02 0.02 0.020.02 0.02 0.02 Imiquimod 3.75 3.75 3.75 3.75 3.75 3.75 Total 100.00100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w % w/w % w/w %w/w % w/w Formulation 187 188 189 190 191 192 Fatty acid* 20.00 20.0020.00 25.00 18.75 25.00 Cetyl alcohol 2.20 2.20 2.20 2.20 2.20 2.70Stearyl alcohol 3.10 3.10 3.10 3.10 3.10 3.80 White 3.00 6.00 6.00 3.005.00 3.00 petrolatum Polysorbate 60 3.40 3.40 3.00 3.40 3.00 3.40Sorbitan 0.60 0.60 1.00 0.50 1.00 0.60 Monostearate Glycerin 2.00 5.005.00 2.00 5.00 2.00 Xanthan gum 0.50 0.50 0.50 0.50 0.50 0.50 Purifiedwater 59.23 53.23 53.23 54.33 55.48 53.03 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 3.75 3.75 3.75 3.75 3.75 3.75Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 193 194 195 196 197 198 Fatty acid*25.00 20.00 20.00 20.00 20.00 21.00 Cetyl alcohol 2.20 4.00 2.20 2.202.20 2.20 Stearyl alcohol 3.10 2.40 3.10 3.10 3.10 3.10 White 3.00 3.405.00 3.00 5.00 5.00 petrolatum Polysorbate 60 3.40 3.80 3.40 3.40 3.403.40 Sorbitan 0.60 1.00 0.60 0.60 0.60 0.60 Monostearate Glycerin 2.003.00 2.00 5.00 5.00 5.00 Xanthan gum 1.00 0.70 0.50 0.50 0.50 0.50Purified water 53.73 55.73 57.23 56.23 54.23 53.23 Benzyl alcohol 2.002.00 2.00 2.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20Propylparaben 0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 3.75 3.75 3.753.75 3.75 3.75 Total 100.00 100.00 100.00 100.00 100.00 100.00Excipients % w/w % w/w % w/w % w/w % w/w % w/w Formulation 199 200 201202 203 204 Fatty acid* 20.00 25.00 22.50 20.00 20.00 22.50 Cetylalcohol 2.20 2.70 2.20 4.00 2.20 2.20 Stearyl alcohol 3.10 3.80 3.102.40 3.10 3.10 White 6.00 3.00 3.00 3.40 5.00 4.00 petrolatumPolysorbate 60 3.00 3.40 3.40 3.80 3.40 3.40 Sorbitan 1.00 0.60 0.601.00 0.60 0.60 Monostearate Glycerin 5.00 2.00 2.00 3.00 2.00 2.00Xanthan gum 0.50 0.50 1.00 0.70 0.50 0.50 Purified water 52.98 52.7855.98 55.48 56.98 55.48 Benzyl alcohol 2.00 2.00 2.00 2.00 2.00 2.00Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben 0.02 0.02 0.020.02 0.02 0.02 Imiquimod 4.00 4.00 4.00 4.00 4.00 4.00 Total 100.00100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w % w/w % w/w %w/w % w/w Formulation 205 206 207 208 209 210 Fatty acid* 20.00 25.0022.50 20.00 20.00 22.50 Cetyl alcohol 2.20 2.70 2.20 4.00 2.20 2.20Stearyl alcohol 3.10 3.80 3.10 2.40 3.10 3.10 White 6.00 3.00 3.00 3.405.00 4.00 petrolatum Polysorbate 60 3.00 3.40 3.40 3.80 3.40 3.40Sorbitan 1.00 0.60 0.60 1.00 0.60 0.60 Monostearate Glycerin 5.00 2.002.00 3.00 2.00 2.00 Xanthan gum 0.50 0.50 1.00 0.70 0.50 0.50 Purifiedwater 52.98 52.78 55.98 55.48 56.98 55.48 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 4.00 4.00 4.00 4.00 4.00 4.00Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 211 212 213 214 215 216 Fatty acid*25.00 15.00 20.00 20.00 20.00 20.00 Cetyl alcohol 2.20 2.00 2.20 2.202.20 2.20 Stearyl alcohol 3.10 2.00 3.10 3.10 3.10 3.10 White 3.00 3.405.00 3.00 5.00 3.00 petrolatum Polysorbate 60 3.40 3.80 3.40 3.40 3.403.40 Sorbitan 0.60 0.2 0.60 0.60 0.60 0.60 Monostearate Glycerin 2.003.00 2.00 5.00 5.00 2.00 Xanthan gum 1.00 0.30 0.50 0.50 0.50 0.50Purified water 53.48 64.08 56.98 55.98 53.98 58.98 Benzyl alcohol 2.002.00 2.00 2.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20Propylparaben 0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 4.00 4.00 4.004.00 4.00 4.00 Total 100.00 100.00 100.00 100.00 100.00 100.00Excipients % w/w % w/w % w/w % w/w % w/w % w/w Formulation 217 218 219220 221 222 Fatty acid* 15.00 15.00 15.00 20.00 15.00 20.00 Cetylalcohol 2.20 2.20 2.20 2.20 2.20 2.20 Stearyl alcohol 3.10 3.10 3.103.10 3.10 3.10 White 1.00 3.00 2.00 3.00 6.00 3.00 petrolatumPolysorbate 60 3.40 3.40 3.40 3.40 3.00 3.00 Sorbitan 0.60 0.60 0.600.60 1.00 1.00 Monostearate Glycerin 2.00 2.00 5.00 2.00 5.00 3.00Xanthan gum 0.50 0.50 0.50 0.50 0.75 0.75 Purified water 65.73 63.7361.73 58.73 57.48 57.48 Benzyl alcohol 2.00 2.00 2.00 2.00 2.00 2.00Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben 0.02 0.02 0.020.02 0.02 0.02 Imiquimod 4.25 4.25 4.25 4.25 4.25 4.25 Total 100.00100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w % w/w % w/w %w/w % w/w Formulation 223 224 225 226 227 228 Fatty acid* 15.00 15.0015.00 25.00 18.0 25.00 Cetyl alcohol 2.20 2.20 2.20 2.20 2.20 2.70Stearyl alcohol 3.10 3.10 3.10 3.10 3.10 3.80 White 3.00 6.00 6.00 3.005.00 3.00 petrolatum Polysorbate 60 3.40 3.40 3.00 3.40 3.00 3.40Sorbitan 0.60 0.60 1.00 0.50 1.00 0.60 Monostearate Glycerin 2.00 5.005.00 2.00 5.00 2.00 Xanthan gum 0.50 0.50 0.50 0.50 0.50 0.50 Purifiedwater 63.73 57.73 57.73 53.83 55.73 52.53 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 4.25 4.25 4.25 4.25 4.25 4.25Total 100.00 100.00 100.00 100.00 100.00 100.00 Excipients % w/w % w/w %w/w % w/w % w/w % w/w Formulation 229 230 231 232 233 234 Fatty acid*25.00 15.00 20.00 20.00 20.0 20.00 Cetyl alcohol 2.20 2.00 2.20 2.202.20 2.20 Stearyl alcohol 3.10 2.00 3.10 3.10 3.10 3.10 White 3.00 3.405.00 3.00 5.00 3.00 petrolatum Polysorbate 60 3.40 3.80 3.40 3.40 3.403.40 Sorbitan 0.60 0.20 0.60 0.60 0.60 0.60 Monostearate Glycerin 2.003.00 2.00 5.00 5.00 2.00 Xanthan gum 1.00 0.30 0.50 0.50 0.50 0.50Purified water 53.23 63.83 56.73 55.73 53.73 58.73 Benzyl alcohol 2.002.00 2.00 2.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20Propylparaben 0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 4.25 4.25 4.254.25 4.25 4.25 Total 100.00 100.00 100.00 100.00 100.00 100.00 *TheFatty acid referenced in this Table 9 can be, for example, linoleic acid(la), stearic acid (sa), palmitic acid (pa), isostearic acid (isa),unrefined oleic acid, (uoa), refined oleic acid, such as super refinedoleic acid (roa), or mixtures thereof.

The work area, all vessels and equipment is initially cleaned prior tocommencing manufacture. A 2 L glass container and paddle stirrer bladeare placed onto a balance and the weight is recorded. The paddle is thenremoved from the vessel. The isostearic acid and benzyl alcohol areweighed directly into the 2 L glass container. The imiquimod is thenweighed into the 2 L glass container and a spatula is used to ensure theimiquimod is wetted with the isostearic acid and benzyl alcohol mixture.The 2 L container is then heated in a water bath to about 55±5° C. whilestirring with a Heidolph mixer (Note: aluminum foil is placed around thetop of the vessel and the paddle for the mixer, to limit evaporation).The solution is visually inspected to confirm the imiquimod has fullydissolved prior to mixing with cetyl alcohol, stearyl alcohol, whitepetrolatum, polysorbate 60 and sorbitan monostearate. Cetyl alcohol,stearyl alcohol, white petrolatum, polysorbate 60 and sorbitanmonostearate are then weighed directly into the 2 L container and mixingis continued at about 55±5° C. until the oil phase is completely insolution. Separately, about 2 L of water are placed into a beaker andheated to 55±5° C. while stirring with a magnetic follower. Briefly,about 500 ml of the heated water is transferred into a 1 L beaker andplaced into the water bath maintained at about 55±5° C. Half of theamount of glycerin required for the final formulation is then weighedinto the beaker along with the total amount of methylparaben andpropylparaben to the water (where both methyl and propyl paraben areweighed into weighing boats first, a pipette is used to remove a portionof the heated water to wash out the weighing boats to ensure totaltransfer of both the propyl- and methylparaben into the aqueous phase).The mixture is continuously stirred at about 55±5° C. (this is theaqueous phase). The remaining glycerin is then added to a 28 ml vial andthe xanthan gum is added and mixed using a small overhead mixer(IKA®-Werke Lab Egg) with paddle attachment for about 10 min. Theglycerin and xanthan mixture are then added slowly into the vortex ofthe aqueous phase, and a further aliquot of about 20 ml of heated wateris used to rinse the vessel out into the water phase to ensure completetransfer. The water phase is then heated and mixed at about 55±5° C.until the xanthan gum mixture is fully and evenly dispersed into theaqueous phase. The temperatures of both the water phase and oil phaseare both maintained at about 55±5° C. The aqueous phase is thentransferred into the oil phase and the speed of the Heidolph mixer isincreased during addition. The mixture is then homogenized on high speedfor about 3 min and transferred immediately back to the Heidolphmixture; however, the contents of the homogenized sample, about 2 L, aremixed at about room temperature and allowed to cool to about 35° C. Thecontainer and contents and the paddle from the overhead mixer are thenre-weighed and the weight of the paddle and 2 L beaker, as determinedabove, are subtracted to determine the total weight of the formulationremaining. The total weight (about 1 kg) of the cream is then made up toweight with heated water (Note: water evaporated during heating, whichneeds to be corrected at this point). The mixture is then transferredback onto the Heidolph mixer at about room temperature and mixed untilthe temperature of the formulation is below about 28° C. The lid of thecontainer is then placed onto the vessel and stored at room temperature.

The lower dosage strength formulations of this Example 23 are believedto be stable and consistent with the specifications for the commerciallyavailable Aldara® 5% imiquimod cream. More preferably, low dosageformulations of this Example 23, especially as to those lower dosagestrength formulations wherein the vehicle comprises an isostearic acidas the fatty acid, are believed to have the following:

(1) Stability. The imiquimod formulations of the present invention, whenthey are measured on HPLC at 25° C./60% RH, 30° C./65% RH and 40° C./75%RH over, one, two, three and six months, demonstrate stabilityconsistent with the Aldara® 5% imiquimod cream;

(2) Degradation Products. No degradation products are detected in theformulations of the present invention, at its current recommendedstorage temperatures of about 4-25° C. In addition, there are nodegradation products detected at any of the temperatures or time pointsmentioned under “Stability” above, when analyzed at about 318 nm;

(3) Homogeneity. The amount of imiquimod that is recovered from theformulations at any of the above-mentioned temperatures and time pointsis between about 90 to about 110% w/w thereby demonstrating goodhomogeneity;

(4) Benzyl Alcohol Content. The formulations of the present inventionare also within specifications for the Aldara® 5% imiquimod cream, i.e.,between 1.0% w/w and 2.1% w/w, at any of the above-mentionedtemperatures and time points as to benzyl alcohol content.

(5) Microscopic Stability. There is no change in the particle size andno crystals are detected in the formulations of the present inventionwhen they are stored at 25° C./60% RH and analyzed over a six monthperiod;

(6) Macroscopic Stability. There are no obvious physical changes in theformulations of the present invention when they are stored at 25° C./60%RH and analyzed over a six month period;

(7) Viscosity. The formulations of the present invention are within therange of the specifications for the Aldara® 5% imiquimod cream, i.e.,between 2000 cPs and 35,000 cPs, when they are stored at 25° C./60% RHand analyzed over a six month period; pH Stability. The formulations ofthe present invention are within the range of the specifications for theAldara® 5% imiquimod cream, i.e., between pH 4.0 and pH 5.5) when theyare stored at 25° C./60% RH and analyzed over a six month period;

(8) Preservative Efficacy Test (“PET”). The formulations of the presentinvention demonstrate sufficient reductions in colony forming unitcounts for each of the organisms with which the formulations areinoculated, i.e., S. aureus, E. coli, Ps. Aeruginosa, C. albicans, andA. niger, at 2-8° C. and 40° C. over a 28 day test period and meet therequirements specified in both the USP and EP.

(9) Imiquimod In vitro Release. The Aldara® 5% imiquimod cream releasesstatistically significant (p<0.05) higher amounts of imiquimod over a 3hour time period in comparison to the lower dosage strength formulationsof the present invention through a synthetic membrane, e.g., Microporouspolyethylene film 3M No. 9711 CoTran™. There is no statisticaldifference (p<0.05) in the total cumulative amount of imiquimod that isreleased from any of the 3.75% w/w imiquimod formulations. There is nostatistical difference (p<0.05) in the total cumulative amount ofimiquimod that is released from any of the 2.5% w/w imiquimodformulations. The Aldara® 5% imiquimod cream also statisticallysignificantly (p<0.05) releases imiquimod at a faster rate over a 3 hourtime period in comparison to the lower dosage strength formulations ofthe present invention through a synthetic membrane, e.g., Microporouspolyethylene film 3M No. 9711 CoTran™. There is no statisticaldifference (p<0.05) between the imiquimod release rates for any of the3.75% w/w imiquimod formulations. There is no statistical difference(p<0.05) between the imiquimod release rates for any of the 2.5% w/wimiquimod formulations. Thus, the greater the amount of imiquimod in aformulation, the faster and greater the total amount of imiquimod thatis released from such formulation that the amount and rate of release ofimiquimod are concentration dependant and that the rates and amounts ofrelease of imiquimod from the formulations of the present invention arelinear and dose proportionate to the Aldara® 5% imiquimod cream;

(10) Imiquimod In vitro Skin Permeation (Franz Cell Study). With respectto statistical analyses, there is no statistical difference between thelower dosage strength formulations of the present invention and theAldara® 5% imiquimod cream as to the amount of imiquimod recovered fromthe receiver fluid, epidermis and dermis combined. Nonetheless, there isa statistically significant (p<0.05) dose proportionate differencebetween the amount of imiquimod recovered from each of the matrices withrespect to the concentration of imiquimod in the lower dosage strengthformulations of the present invention and the Aldara® 5% imiquimod creamfor both un-absorbed and stratum corneum. Thus there is a linear doserelease between the amount of imiquimod that is applied and recovered ineach of the matrices, i.e., receiver fluid, unabsorbed dose, stratumcorneum, epidermis and dermis.

ANOVA statistical analysis at 95% confidence level is used to analyzethe stability data generated, including the data generated for themembrane and skin permeation experiments.

It is also believed that the formulations of the present invention,including the formulations identified in this Example 23, haveHydrophilic-lipophilic balance (HLB) values between about 12 and 15, andmore preferably between about 12.4 and about 13.4.

I. Physical Characterization and Testing

The following is conducted for physical characterization of lower dosagestrength imiquimod formulations, e.g., formulations identified in Table12 and Table 18, and for testing lower dosage strength imiquimodformulations, e.g., imiquimod formulations identified in Tables 13-17.

(A) Analytical Method—HPLC Assay

A summary of an HPLC method is provided in Table 10.

TABLE 10 Summary of HPLC Methodology HPLC System HPLC 9. Waters 265(Alliance Separations module), Water 996 (Photodiode array detector),CPU (Compaq), Software - Microsoft Windows NT Version 4.00.1381 andAnalysis software - Millenium³² Version 4.00.00.00 Column SupelcosilLC-8-DB (5 mm, 15 × 0.46 cm) Guard Column Supelguard LC-8-DB 2 cmDetection UV at 258 nm Sample Temperature 25° C. Column Temperature 25°C. Flow Rate 2 ml/min Mobile Phase 72:28 aqueous:ACN (1% TEA solution,0.2% Octyl Sodium Sulfate, adjusted to pH 2.0 with H₃PO₄ InjectionVolume 20 μl Run Time 12 min Needle Wash 10:90 0.1N HCI:water

(B) Preparation of HPLC Reagents

(1) Mobile Phase:

About 2.0 g octyl sodium sulfate (OSS) is weighed into a large beakerand is mixed with about 990 ml Milli-Q ultrapure water and about 10.0 mlof triethylamine (TEA). The mixture is sonicated and stirred for about 5min to dissolve the solids. A pH meter is then placed in the mixture andthe pH of the OSS/TEA solution is adjusted to about 2.0 withconcentrated H₃PO₄, stirring continuously during the adjustingprocedure. The entire mixture is then filtered through a 0.2 μm filter.The filtrate is mixed with acetonitrile (HPLC grade) in the ratio ofabout 72:28 aqueous:acetonitrile by volume.

(2) Sample Diluent

About 250 ml acetonitrile (HPLC grade), about 740 ml purified water andabout 10 ml of concentrated HCl are mixed together in a 1 L volumetricflask.

(3) Receiver Fluid

About 100 ml of a commercially available standardized 1N HCl solution isdiluted to about 1000 ml with Milli-Q ultra pure water.

(4) Standards

Imiquimod standards are prepared, as described under Sample Diluent andReceiver Fluid, for stability test and receiver for membrane releasetests. Initially, a stock solution of imiquimod is prepared bydissolving about 25 mg of imiquimod into about 50 ml of solvent (eitherSample Diluent or Receiver Fluid) to give a concentration of about 500μg/ml in Sample Diluent or Receiver Fluid.

A calibration range as shown in Table 11 is prepared for each HPLC run.

TABLE 11 Preparation of Calibration Standards Volume of stock solutionFinal concentration of Test (ml) Volume of diluent Item (μg/m1) 10 0 5005 5 250 4 6 200 2 8 100 1 9 50 0.5 9.5 25 0.2 9.8 10 0.1 9.9 5

(5) Combination Standard

The following combination standard solution is also prepared; whereby,about 500 mg of methylparaben and about 50 mg propylparaben are weighedinto a single 250 ml volumetric flask and is diluted to volume withsample diluent above, to form the parabens solution. In addition, about500 mg of imiquimod and about 200 mg benzyl alcohol are also weighedinto a single 100 ml volumetric flask and about 10 ml of the parabenssolution is then transferred into the imiquimod/benzyl alcoholvolumetric which is made up to volume with diluent and is sonicated todissolve fully.

(6) Impurity Standards

Impurity standards are prepared separately at a concentration of about50 p.g/ml in Sample Diluent and are analyzed in each HPLC run. Theimpurity standards that are included in each HPLC run are as follows:

N-propyl imiquimod

N-methyl imiquimod

4-hydroxyimiquimod

4-chloro imiquimod

TABLE 12 2.5% Imiquimod Formulations 3.75% Imiquimod Formulations 235236 237 238 239 240 241 242 243 244 181 245 % w/w % w/w % w/w % w/w %w/w % w/w % w/w % w/w % w/w % w/w % w/w % w/w Excipients Isostearic acid15 10 15 10 15 15 15 20 15 20 15 20 Cetyl alcohol 2 4 4 2 2 4 2 2 2 2 44 Stearyl alcohol 2 2 2 2.4 2.4 2.4 2 2 2.4 2.4 2.4 2.4 White 3.4 3.42.8 2.8 3.4 2.8 3.4 2.8 3.4 2.8 2.8 3.4 petrolatum Polysorbate 60 3.83.8 3 3.8 3 3.8 3 3.8 3 3 3 3.8 Sorbitan 0.2 1 1 1 1 0.2 1 1 0.2 0.2 1 1Monostearate Glycerine 3 1 3 3 1 1 3 1 1 3 1 3 Xanthan gum 0.3 0.3 0.70.3 0.7 0.3 0.3 0.7 0.7 0.3 0.3 0.7 Purified water 65.58 69.78 63.7869.98 66.78 65.78 64.33 60.73 66.33 60.33 64.53 55.73 Benzyl alcohol 2 22 2 2 2 2 2 2 2 2 2 Methylparaben 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.20.2 0.2 0.2 Propylparaben 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.020.02 0.02 0.02 Imiquimod 2.50 2.50 2.50 2.50 2.50 2.50 3.75 3.75 3.753.75 3.75 3.75 Total amount 100.00 100.00 100.00 100.00 100.00 100.00100.00 100.00 100.00 100.00 100.00 100.00 (g) HLB Values 14.4 12.8 12.412.8 12.4 14.4 12.4 12.8 14.3 14.3 12.4 12.8

In Table 13, fifteen 2.5% w/w imiquimod formulations are manufactured in100 g batches. Each of the fifteen formulations are assessed formacroscopic and microscopic appearance, as discussed hereinafter.

TABLE 13 Imiquimod 246 110 116 247 117 248 249 250 113 Formulations %w/w % w/w % w/w % w/w % w/w % w/w % w/w % w/w % w/w Excipients Cetylalcohol 2.20 2.20 2.20 2.20 2.20 2.20 2.20 2.20 2.20 Stearyl alcohol3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10 3.10 White 15.50 3.00 6.00 8.506.00 6.00 8.50 3.00 6.00 petrolatum Polysorbate 60 3.40 3.40 3.40 3.403.00 4.25 3.00 3.40 3.00 Sorbitan 0.60 0.60 0.60 0.60 1.00 0.75 1.000.60 1.00 Monostearate Glycerine 2.00 2.00 5.00 5.00 5.00 5.00 5.00 2.005.00 Xanthan gum 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.75 Purifiedwater 52.98 65.48 59.48 61.98 59.48 58.48 61.98 55.48 59.23 Benzylalcohol 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 Methylparaben 0.200.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben 0.02 0.02 0.020.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 2.50 2.50 2.50 2.50 2.50 2.502.50 2.50 2.50 Total amount 100.00 100.00 100.00 100.00 100.00 100.00100.00 100.00 100.00 (g) HLB Values 13.4 13.4 13.4 13.4 12.4 13.4 12.413.4 12.4 Imiquimod 251 252 253 254 120 121 Formulations % w/w % w/w %w/w % w/w % w/w % w/w Excipients Cetyl alcohol 2.20 2.20 2.20 2.20 2.702.20 Stearyl alcohol 3.10 3.10 3.10 3.10 3.80 3.10 White 6.00 5.00 5.005.00 3.00 3.00 petrolatum Polysorbate 60 3.00 3.40 3.40 3.00 3.40 3.40Sorbitan 1.00 0.60 0.60 1.00 0.60 0.60 Monostearate Glycerine 5.00 5.005.00 5.00 2.00 2.00 Xanthan gum 1.00 0.50 0.50 0.60 0.50 1.00 Purifiedwater 58.98 65.48 62.98 62.98 54.28 54.98 Benzyl alcohol 2.00 2.00 2.002.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 Propylparaben0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 2.50 2.50 2.50 2.50 2.50 2.50Total amount 100.00 100.00 100.00 100.00 100.00 100.00 (g) HLB Values12.4 13.4 13.4 12.4 13.4 13.4

TABLE 14 2.5% Imiquimod 110 116 117 250 254 120 121 235 123 124 125 126Formulations % w/w % w/w % w/w % w/w % w/w % w/w % w/w % w/w % w/w % w/w% w/w % w/w Excipients Isostearic acid 15.00 15.00 15.00 25.00 12.525.00 25.00 15 20.00 20.00 20.00 20.00 Cetyl alcohol 2.20 2.20 2.20 2.202.20 2.70 2.20 2 2.20 2.20 2.20 2.20 Stearyl alcohol 3.10 3.10 3.10 3.103.10 3.80 3.10 2 3.10 3.10 3.10 3.10 White 3.00 6.00 6.00 3.00 5.00 3.003.00 3.4 5.00 3.00 5.00 3.00 petrolatum Polysorbate 60 3.40 3.40 3.003.40 3.00 3.40 3.40 3.8 3.40 3.40 3.40 3.40 Sorbitan 0.60 0.60 1.00 0.601.00 0.60 0.60 0.2 0.60 0.60 0.60 0.60 Monostearate Glycerine 2.00 5.005.00 2.00 5.00 2.00 2.00 3 2.00 5.00 5.00 2.00 Xanthan gum 0.50 0.500.50 0.50 0.50 0.50 1.00 0.3 0.50 0.50 0.50 0.50 Purified water 65.4859.48 59.48 55.48 62.98 54.28 54.98 65.58 58.48 57.48 55.48 60.48 Benzylalcohol 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2 2.00 2.00 2.00 2.00Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.2 0.20 0.20 0.20 0.20Propylparaben 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.020.02 Imiquimod 2.50 2.50 2.50 2.50 2.50 2.50 2.50 2.50 2.50 2.50 2.502.50 Total 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00100.00 100.00 100.00 100.00 HLB Values 13.4 13.4 12.4 13.4 12.4 13.413.4 14.4 13.4 13.4 13.4 13.4

TABLE 15 3.75% Imiquimod 182 188 189 183 184 255 193 245 195 256 197Formulations % w/w % w/w % w/w % w/w % w/w % w/w % w/w % w/w % w/w % w/w% w/w Excipients Isostearic acid 20.00 20.00 20.00 25.00 18.75 25.0025.00 20 20.00 20.00 20.00 Cetyl alcohol 2.20 2.20 2.20 2.20 2.20 2.702.20 4 2.20 2.20 2.20 Stearyl alcohol 3.10 3.10 3.10 3.10 3.10 3.80 3.102.4 3.10 3.10 3.10 White petrolatum 3.00 6.00 6.00 3.00 5.00 3.00 3.003.4 5.00 3.00 5.00 Polysorbate 60 3.40 3.40 3.00 3.40 3.00 3.40 3.40 3.83.40 3.40 3.40 Sorbitan 0.60 0.60 1.00 0.60 1.00 0.60 0.60 1 0.60 0.600.60 Monostearate Glycerine 2.00 5.00 5.00 2.00 5.00 2.00 2.00 3 2.005.00 5.00 Xanthan gum 0.50 0.50 0.50 0.50 0.50 1.00 1.00 0.7 0.50 0.500.50 Purified water 59.23 53.23 53.23 54.23 55.48 53.73 53.73 55.7357.23 58.23 54.23 Benzyl alcohol 2.00 2.00 2.00 2.00 2.00 2.00 2.00 22.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.2 0.200.20 0.20 Propylparaben 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.020.02 0.02 Imiquimod 3.75 3.75 3.75 3.75 3.75 3.75 3.75 3.75 3.75 3.753.75 Total 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00100.00 100.00 100.00 HLB Values 13.4 13.4 12.4 13.4 12.4 13.4 13.4 12.813.4 13.4 13.4

In Table 16, compositions for Aldara® 5% imiquimod cream and 1%imiquimod cream formulations are shown. Also shown in the Table 16, arefour placebo formulations Pbo1, Pbo2, Pbo3 and formulation Pbo4.

TABLE 16 3M Aldara ® Placebos (5% Bulk) 257 (1%) Pbo1 Pbo2 Pbo3 Pbo4Formulations % w/w % w/w % w/w % w/w % w/w % w/w Excipients Isostearicacid 25.00 25.00 20.00 20.00 20.00 20.00 Cetyl alcohol 2.20 2.40 2.202.20 2.20 2.20 Stearyl alcohol 3.10 3.40 3.10 3.10 3.10 3.10 Whitepetrolatum 3.00 3.00 5.00 3.00 5.00 3.00 Polysorbate 60 3.40 3.40 3.403.40 3.40 3.40 Sorbitan Monostearate 0.60 0.60 0.60 0.60 0.60 0.60Glycerin 2.00 2.00 2.00 5.00 5.00 2.00 Xanthan gum 0.50 0.50 0.60 0.600.50 0.50 Purified water 52.98 58.48 80.98 59.98 57.98 62.98 Benzylalcohol 2.00 2.00 2.00 2.00 2.00 2.00 Methylparaben 0.20 0.20 0.20 0.200.20 0.20 Propylparaben 0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 5.001.00 0.00 0.00 0.00 0.00 Total 100.00 100.00 100.00 100.00 100.00 100.00HLP Values 13.37 13.37 13.37 13.37 13.37 13.37

(C) Uniformity/Homogeneity

Following a 1 kg batch manufacturing process as described in thisExample 23, 3×150 mg samples (top, middle and bottom) are removed fromeach 1 kg bulk batch using a positive displacement pipette and areextracted and are analyzed as described in Section, entitled “ImiquimodContent” described hereinafter.

(D) Preparation of Stability Samples

Each of the 1 kg batches are sub-aliquoted individually into 21×60 mlglass powder jars, where:

-   -   5×50 g (25° C./60% RH t=0 h, 1 month, 2 months, 3 months, 6        months)    -   5×50 g (30°/65% RH-t=0 h, 1 month, 2 months, 3 months, 6 months)    -   5×50 g (40° C./75% RH-t=0 h, 1 month, 2 months, 3 months, 6        months)    -   1×60 g (PET sample, placed at 2-8° C.)    -   1×20 g (placed at 2-8° C.)    -   1×20 g (placed at −20° C.)    -   The remaining formulation, is divided into 3 additional aliquots        and each is placed at 25° C./60% RH, 30°/65% RH and 40° C./75%        RH.

All batches are characterised based on the protocols that are shown inSection entitled Protocol for the Assessment of Formulations. Once eachaliquot is removed from the relevant stability conditions at each timepoint; the remaining aliquot from each sample is placed in a fridge at2-8° C. for future reference if required.

Following the 1 month stability time point, the benzyl alcohol contentof the formulations are monitored; for all subsequent time points, theplacebo formulations are analyzed by HPLC. Thus, there are no t=0measurements for benzyl alcohol content for placebo formulations Pbo1,Pbo2 and Pbo3.

(E) Protocol for the Assessment of Formulations

The protocols that are used for the assessment of the formulations areas follows:

(1) Macroscopic Appearance

Macroscopic appearance is determined by visual examination of thephysical characteristics which include appearance and texture of eachcream. Macroscopic appearance is performed at each time point (t=0, 1,2, 3 and 6 months) for the 25° C. stability samples, as follows:

-   -   Using a medium Granton® pallet knife, a small aliquot of sample        (approximately 1 to 2 g) is removed from its container and is        placed on the surface of a large Granton® pallet knife.    -   The medium Granton® pallet knife is then used to smooth the        cream over the surface of the large Granton® pallet knife, by        using a backward and forward motion of the spatula until a        visually uniform layer of cream is obtained on the large        Granton® pallet knife.    -   Visual observations of the cream are recorded which are based        on, the presence of lumps, graduals or ease of spread over the        surface of the spatula.

(2) Microscopic Appearance

Formulations are viewed under a light microscope (Leica DME FD198536Light Microscope), to determine particle size, uniformity and theabsence of particulates. Digital images of each formulation are taken ateach time point (t=0, 1, 2, 3 and 6 months) for the 25° C. stabilitysamples, as follows:

-   -   The microscope is set up so that the camera (Nikkon Cool Pix        4500 digital camera) is attached to the relay lens of the        microscope and the 40× objective lens is set into place to view        the sample. Camera settings: Image size: 1280×960 pixels, Image        quality: Fine.    -   A small droplet of the formulation to be viewed is placed onto a        microscope slide (Fisher-brand microscope slides, Cat No. 7101)        using a micro-spatula. The microscope slide is then covered        using a cover glass (Fisher-brand cover glass, width: 22-32 mm,        thickness: 0.13-0.17 mm).    -   The microscope slide with the formulation is then placed under        the 40× objective. Using the fine adjustment knob of the light        microscope, the slide is brought into sharper focus to get a        clear view.    -   Once a clear distinct view is obtained, pictures are taken (×400        magnification).    -   The particle sizes of formulations prepared are determined using        a graticule (Olympus, Objective Micrometer, 0.01 mm). Overall        uniformity and particle size are measured using the scale on the        calibrated graticule shown in FIG. 55. Five random locations on        each slide for each formulation are chosen to assess uniformity        and particle size.

(3) Imiquimod Content

The imiquimod content of the formulations is measured at each time point(t=0, 1, 2, 3 and 6 months) for the 25° C. and 40° C. stability samples.The 30° C. stability samples are removed from the stability cabinet ateach time point and placed at about 2-8° C. for future reference, asfollows:

-   -   About 150 mg of the formulation is removed from each sample and        is transferred into a 50 ml volumetric flask.    -   About 30-40 ml of diluent (about 250 ml acetonitrile (HPLC        grade), about 740 ml purified water and about 10 ml of        concentrated HCl are mixed together in a 1 L volumetric flask)        is then added to the volumetric flask containing the aliquot of        the formulation.    -   The sample is then vortex mixed for approximately 1 min or until        the formulation has visibly completely dispersed into the        diluent.    -   The sample is then sonicated for about 5 min and then is left to        cool to room temperature.    -   The sample is then filled to volume with diluent and is mixed by        inverting the volumetric flask.    -   This step is followed by filtration through a 0.45 mm filter        directly into a 2 ml HPLC vial and the cap crimped.    -   The sample is then analysed on the HPLC using the method        described in Section entitled Analytical Method—HPLC Assay        described above, with the standard solutions as described above        in Sections entitled Standards Combination Standard and Impurity        Standard. This method also allows for the detection and        measurement of benzyl alcohol.

(4) Related Substances/Degradation Products

Following the extraction and analysis, as described above underImiquimod Content, the chromatograms for each formulation are comparedto those generated for the impurity standards, as described above underImpurity Standards, to identify if there are any degradation peakspresent. As the preservatives have similar retention times as thedegradation products, the chromatograms are viewed at an absorbance of318 nm wavelength at which the preservatives do not absorb to confirmthe absence of degradation products.

(5) pH Measurements

The pH of the formulations are measured at each time point (t=0, 1, 2, 3and 6 months). The pH measurement protocol is as follows:

-   -   A small sample of the formulation is applied on to the surface        of a strip of pH paper (Fisher-brand pH paper: FB33045, Range pH        0.5-5.5) and is spread evenly over the surface using a spatula.    -   The pH paper with the formulation on it is then left for 10 min        to ensure that the paper does absorb the cream (which is        confirmed by a color change).    -   The pH of the formulation is then determined by comparing the        color on the strip of pH paper with a range of colors (color        chart) that are provided with the Fisher-brand pH paper.

(6) Viscosity from Flow Curve (Rheology Bohlin CVO Measurements)

The rheology of the formulations are measured at each time point (t=0,1, 2, 3 and 6 months) for the 25° C. stability samples.

(7) Rheology Oscillation Methodology (Bohlin CVO)

The Crossover and G^(I) values of the ICH stability samples are measuredfor all the t=0 samples. See e.g., Tables 18 and 26. The ‘crossover’point is an indication of the elastic structure of the formulation and ahigh cross over point indicates that more force is required to breakdownthe formulation thus providing an indication for longer term stabilityof the cream formulations. The G^(I) value is a measurement of theelastic part of the formulation, whereby a high G^(I) value indicates amore rigid formulation which ‘recovers’ more easily from applied shearstress.

(8) Viscosity (Brookfield) Measurements

The viscosity of the formulations is measured at each time point (t=0,1, 2, 3 and 6 months) for the 25° C. stability samples.

(9) Preservative Efficacy Test Protocol

The preservative efficacy test is performed on formulations 110, 126,Pbo4 and 182 which are stored at about 2-8° C. and about 40° C. forabout 3 months. Preservative efficacy testing is carried out accordingto the procedure described in line with the methodology described in theUSP 2007 and EP 2007. The time points, at which the inoculated samplesare tested are: Oh, 24 h, 48 h, 7 days, 14 days, 21 days and 28 days.

Method validation is performed using Staphylococcus aureus cultures toconfirm the neutralizing effect of D/E broth, for this purpose 110 and182 are used to confirm neutralization of the preservatives.

II. Test Item Release Studies Through Synthetic Membranes

(A) In Vitro Screening of Release Profiles Through Synthetic Membranes

The release of imiquimod from 13 formulations (n=4 for each) arecompared using methodology based on the principles of the FDA, SUPAC-SSguidelines. The formulations that are tested included: 3M's Aldara® 5%imiquimod cream 1 kg bulk sample, Aldara® 5% imiquimod cream sachet(commercial product), Graceway's Aldara® 5% imiquimod cream lkg batch,and formulations 257 (1%), 123, 250, 125, 110, 182, 195, 256, 197 and183. The protocol for the investigation is as follows:

A synthetic membrane (Microporous polyethylene film 3M No. 9711 CoTran™)is mounted in a small Franz cell (refer to FIG. 56) with a receiverfluid (0.1 N HCl) to ensure sink conditions (is equilibrated for aminimum of 30 min prior to dosing). An infinite dose of formulation (230to 250 μl is dispensed using a calibrated positive displacement pipette)is applied to the membrane (using the pipette tip to gently spread overthe surface) and the diffusion of imiquimod that is measured over time(n=4 per formulation). Briefly 200 μl of the receiver fluid is removedusing a 250 μl Hamilton syringe at each time point (0, 15, 30, 60, 120and 240 min) and is analysed on the HPLC using the method, as describedunder Analytical Method—HPLC Assay. The sample of receiver fluid isremoved at each time point and is replaced with fresh pre-warmed (32°C.) receiver fluid.

III. In vitro Skin Permeation Study

(A) Analytical Methods

(1) Liquid Scintillation Method Details

Samples are added to a scintillation vial and about 4 ml ofscintillation cocktail (Hionic-fluor) is added. The vial is capped andis shaken using a vortex mixer until the sample is mixed with thescintillation cocktail. The scintillation vials are then loaded intoracks before analysing on the scintillation counter, using the settingslisted as follows.

Model of scintillation counter: Beckman LS 5000 CE Isotope setting: C₁₄Counting time: 5 min Calculation mode: SL DPM Count samples: 1 timesReplicates: 1 Quench monitor: Yes

(B) Radioactive purity of Imiquimod ¹⁴C

1. Preparation of Stock

The radio-labelled material is as follows:

Imiquimod stock (^(C)14): Specific activity of about 57 mCl/mmol with aradiochemical purity of about 99.2% is supplied as a powder in aborosilicate multi-dose vial with additional screw cap.

Working stock solutions are prepared by addition of 1 ml isostearic acidto the imiquimod powder using a needle and syringe inserted through theseptum of the vial. The screw cap is then replaced securely and the vialshaken on a vortex mixer until all the imiquimod dissolves in theisostearic acid. The homogeneity is also confirmed. This results in astock solution containing about 1000 Ci/ml.

(C) Preparation of Formulations

The method for the preparation of about a 100 g radioactive batch is asfollows:

-   -   The glass container and mixer paddle attachment are placed onto        a balance and the weight is recorded before the container and        paddle are removed.    -   The amount of imiquimod required for the formulation is added by        weight and the remaining isostearic acid (minus 1.38 g) and        benzyl alcohol are added to the container.    -   The entire mixture is heated in a water bath at about 55±5° C.        while stiffing with a small over head mixer (IKA®-Werke Lab Egg)        and paddle attachment.    -   Cetyl alcohol, stearyl alcohol, white petrolatum, polysorbate 60        and sorbitan monostearate are added into the beaker and mixed at        about 55±5° C. until the oil phase is completely in solution.    -   Separately, about 200 ml of water is heated in a beaker to about        55±5° C. while stirring with a magnetic follower.    -   About 50 ml of the heated water is transferred into a beaker and        is placed in a water bath maintained at about 55±5° C. and half        the glycerine, methyl hydroxyparabens and propyl hydroxyparabens        are added (where both methyl and propyl parabens are weighed        into weighing boats first) to the water and is stirred at about        55±5° C. (this is the aqueous phase).    -   The remaining glycerine is added to a 28 ml vial with the        xanthan gum and is mixed using a small over head mixer        (IKA®-Werke Lab Egg) with paddle attachment for about 10 min.    -   The glycerine and xanthan mixture are then added into the vortex        of the aqueous phase, using about a 5 ml aliquot of heated water        to rinse the vessel out into the water phase.    -   Mixing of the water phase is continued for at least about 5 min.    -   The aqueous phase is transferred into the oil phase, increasing        the stirring speed during addition.    -   The mixture is stirred on high speed maintaining the temperature        at about 55±5° C. for 30 min.    -   The vessel is removed from the mixer and is homogenised using        the 1 cm head for about 3 min.    -   Mixing is continued while cooling to about 35° C. and the total        weight of the cream is made up to weight with heated water. The        mixture is transferred to the overhead stirrer and cooling and        stiffing is continued to about 25° C.    -   The formulations are then aliquoted in to screw top vials and        are sealed with Parafilm® placed around the screw top lid.    -   About 9.862 g of the formulation is weighed into a vial and is        placed in a water bath at about 5° C. About 138 mg of        radio-labelled working stock solution is then added to the        formulation and the formulation is thoroughly mixed using a        spatula while cooling.

(D) Homogeneity Control

Following manufacturing of the formulations, the following test isperformed:

For each of the formulations, three aliquots (top, middle and bottom ofbatch) of approximately 5 mg is exactly weighed directly into ascintillation vial, where about 4 ml of scintillation cocktail is added.All of the samples are then directly quantified on the LiquidScintillation Counter (“LSC”) to confirm homogeneity within ±10%.

(E) Franz Cell Study

The method involves the use of full thickness human skin that is mountedin a Franz cell with about a 0.01 N hydrochloric acid as receiver fluidto ensure sink conditions. A dose of formulation equivalent to about 10mg/cm² is applied to the membrane and the diffusion of imiquimod ismeasured over time. Human skin from cosmetic reduction surgery is used.Subcutaneous fat is removed mechanically prior to preparation of theskin section for the study. The formulations (6

) are applied to the surface of the membrane using a positivedisplacement pipette. The investigation is performed in severalexperiments. Two skin donors are used randomly and are assigned acrossall experiments so that each formulation is tested on both skin donors.Each experiment consists of two randomly assigned formulations (n=6cells per formulation) and two comparator formulations (n=6 cells percomparator). The receptor compartment of the Franz cells is then filledwith the receiver fluid and the cells are fixed in a water bathmaintained at about 37° C. The receptor compartment contents arecontinuously agitated by small magnetic followers. At t=1, 8 and 24 h,samples of receiver fluid are taken from the receptor compartment, andare replaced with fresh receiver fluid and are assayed by scintillationcounting.

(F) Mass Balance

At the end of the experiment, a mass balance experiment is carried out,where the amount of ¹⁴C imiquimod remaining in the donor compartment,surface residue, Stratum corneum (SC), remaining epidermis, dermis andreceiver compartment is quantified. This method involves removal of theSC by tape stripping and processing of the remaining epidermal layer anddermis using standard procedures. The protocol for the mass balance isas follows:

Unabsorbed dose: The surface of each Franz cell donor chamber is wipedgently with a cotton bud using 5 clockwise and anti-clockwise movements.This procedure is repeated on 4 occasions using alternate wet (receiverfluid) and dry cotton buds. The cotton buds are added to scintillationcocktail before analysis. Two tape strips are removed from the skin andthese are regarded as unabsorbed formulation and included in the totalsurface activity. The Stratum corneum) (SC) is removed by carefully tapestripping the membrane ten times using Scotch adhesive tape.Collectively, each tape is placed into a scintillation vial to which 4ml of scintillation cocktail are added before analysis. Epidermal layer:The remaining section of the epidermis (following tape stripping) iscarefully removed from the dermis with a scalpel. The epidermis isplaced into a glass vial containing 2 ml of Soluene 350 and is incubatedat about 50° C. for about 72 h before analysis by LSC. The remainingdermal layer is placed in to a glass vial containing about 2 ml ofSoluene 350 and is incubated at about 50° C. for about 72 h beforeanalysis by LSC.

(G) Analysis of Data

ANOVA statistical analysis at a 95% confidence level is used to analysethe data generated for the membrane release and skin permeationexperiments.

An example of the ANOVA statistical analysis is as follows:

Individual 95% CIs For Mean Base on Pooled StDev Level N Mean StDev

Formulation X 4 4605.5 626.9

Formulation Y 4 1862.8 185.9

Formulation Z 4 1845.6 206.4

Whereby, no significance (p>0.05) is shown by two overlapping histograms(e.g. Y and Z), whereas a significant difference (P≦0.05) can beidentified by two histograms which don't overlap (e.g. X and Y and X andZ). The width of the each histogram is a reflection of the pooledstandard deviation from all data sets.

IV. Results and Discussion

(A) Degradation Product Analysis

It is discovered that the preservatives (benzyl alcohol, methylparabenand propylparaben) at about 318 in the imiquimod formulations can not bedetected. Thus, by analysing the imiquimod formulations at thiswavelength, it permits the detection of degradation products, if any, inthe presence of preservatives. However, no degradation products areidentified at about 318 nm for any of the imiquimod formulations testedup to and including the 6 month stability time point at about 25° C. andabout 40° C.

In Table 17 and FIG. 57, they show a summary of the findings, wherebysimple microscopic analysis of the imiquimod formulations identifyformulations with inconsistent particle size and large aggregation ofmaterial. Summary and composition of lower dosage strength imiquimodformulations are listed in Table 13 and Table 14.

TABLE 17 246 110 116 247 117 248 249 250 113 % w/w % w/w % w/w % w/w %w/w % w/w % w/w % w/w % w/w Viscosity high High high high high high highlow high (visual) Appearance lumpy Smooth smooth smooth smooth smoothsmooth smooth slightly (spatula) textured pH 5 5 5 5 4.5 4.5 5 4 5 G¹(Pa) 3639 1150.5 1504 1093 1740.5 5235 1364.5 171.5 642 crossover 29.514.5 20.5 16 21.5 none 21.5 13 21.5 (o¹) Microscope v. bad Ok good badgood v.bad bad good bad 251 252 253 254 120 121 % w/w % w/w % w/w % w/w% w/w % w/w Viscosity high high Medium- high very medium (visual) highhigh low Appearance Textured smooth smooth matt, matt, smooth (spatula)smooth smooth pH 5 5 5 5 4.5 4.5 G¹ (Pa) 943 626.5 567 2285.5 5231 304.5crossover 29.25 19 15 21.5 20.5 29.75 (o¹) Microscope bad ok bad ok okgood

TABLE 18 Physical Characteristics of 12 Lower Dosage Strength ImiquimodFormulations, i.e., Formulations 181, 235, 236, 237, 238, 239, 240, 241,242, 243, 244 and 245. 235 236 237 238 239 240 241 242 243 244 181 245Excipients % w/w % w/w % w/w % w/w % w/w % w/w % w/w % w/w % w/w % w/w %w/w % w/w Isostearic acid 15 10 15 10 15 15 15 20 15 20 15 20 Cetylalcohol 2 4 4 2 2 4 2 2 2 2 4 4 Stearyl alcohol 2 2 2 2.4 2.4 2.4 2 22.4 2.4 2.4 2.4 White 3.4 3.4 2.8 2.8 3.4 2.8 3.4 2.8 3.4 2.8 2.8 3.4petroleum Polysorbate 60 3.8 3.8 3 38 3 3.8 3 3.8 3 3 3 3.8 Sorbitan 0.21 1 1 1 0.2 1 1 0.2 0.2 1 1 Monostearate Glycerin 3 1 3 3 1 1 3 1 1 3 13 Xanthan gum 0.3 0.3 0.7 0.3 0.7 0.3 0.3 0.7 0.7 0.3 0.3 0.7 Purifiedwater 65.58 69.78 63.78 69.98 66.78 65.78 64.33 60.73 66.33 60.33 86.5355.73 Benzyl alcohol 2 2 2 2 2 2 2 2 2 2 2 2 Methylparaben 0.2 0.2 0.20.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Propylparaben 0.02 0.02 0.02 0.020.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 Imiquimod 2.50 2.50 2.50 2.502.50 2.50 3.75 3.75 3.75 3.75 3.75 3.75 Total amount 100.00 100.00100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00(g) HLB Values 14.39 12.78 12.35 12.78 12.35 14.39 12.35 12.78 14.2614.26 12.35 12.78 Modification: multi multi multi multi multi multimulti multi multi multi multi multi Viscosity low/ high high medium med/high Medium- Medium Medium- Medium- Very High High med high High Lowhigh pH 4.7 4.7 4.7 6 4.7 4.7 5.0 4.7 4.7 4.5 4.7 4.5 G 294.37 1527.65639.345 467.78 552.61 924.075 116.18 416.65 8767 65.425 2514.25 1280.05crossover 9.5 25.25 10.5 17.75 12 25.5 13.75 18.5 none 11.75 36 22.5microscope v. good ok, but bad good, but bad bad- good with very ok goodvery good good particles? particles? particles? bubbles good Appearance/glossy, smooth, slight glossy, v. smooth, glossy, glossy, glossy,glossy, smooth with glossy, Spatula v slight matt, texture, smoothglossy matt slightly textured slightly very a matt smooth, texture,slightly matt & v. textured with textured, slightly appearance withmatt, aerated does smooth with some some very textured some does smoothaeration aeration aerated aeration smooth out out

(B) Scale-Up and ICH Stability

1. Homogeneity

In Table 19, formulations 245, 121 and 193 show signs of phaseseparation. All the other formulations in Table 19 show goodhomogeneity, and are subsequently sub-aliquoted and placed on stabilityas described above under Preparation of Stability Samples.

TABLE 19 Homogeneity Results from 1 kg batches, where Samples areRemoved from Top Middle and the Bottom of the Batch for Comparison ofHomogeneity. Formulation % Recovery % CV 3M Aldara ® 5% Batch 102.69 ±2.29 2.23 257 (1%) 100.29 ± 0.68 0.68 197  96.81 ± 2.15 2.22 183  97.56± 0.48 0.50 245  91.08 ± 12.80 14.06  182  97.68 ± 0.73 0.75 189  98.32± 0.92 0.94 184  98.37 ± 1.61 1.63 193  97.21 ± 0.22 0.23 188  98.95 ±2.48 2.51 195  99.66 ± 0.70 0.70 255  99.46 ± 0.49 0.49 256  98.80 ±0.75 0.76 Graceway Aldara ® 5% Imiquimod 102.74 ± 1.26 1.23 110 101.43 ±0.63 0.62 116 100.39 ± 0.18 0.18 117 100.49 ± 0.64 0.64 250  99.98 ±0.37 0.37 254  98.70 ± 0.21 0.21 120 100.02 ± 0.34 0.34 121 106.22 ±0.09 0.09 235 101.04 ± 0.21 0.21 123 101.75 ± 0.28 0.28 124  95.00 ±0.32 0.34 125 101.12 ± 0.12 0.12 126 102.37 ± 0.58 0.57 Pbo1 N/A N/APbo2 N/A N/A Pbo3 N/A N/A Pbo4 N/A N/A

(C) Stability

1. Stability of Imiquimod in Formulations

In Table 20, imiquimod in the formulations is stable at both about 25°C. and about 40° C. over an about six month period, although the resultsfor three and six months at both about 25° C. and about 40° C. lookconsistently higher than previous time points. This could be attributedto a small amount of water evaporation from the containers. In addition,all samples are consistent with the commercially supplied Aldara® 5%imiquimod cream sample. There are no degradation products detected inany of the samples in Table 20 at any of the temperatures and timepoints when analyzed at about 318 nm. With reference to formulationspecification, the specification amount of imiquimod that is recoveredfrom the samples in Table 20 is between about 90%-110% w/w, therebyconfirming that the samples fall within their target specification. Inother words, and by way of example, the specification amount ofimiquimod that is recovered from preferred 2.5% imiquimod formulationsof the present invention will fall within between about 2.25% and about2.75% w/w and the amount of imiquimod that is recovered from preferred3.7.5% imiquimod formulations of the present invention will fall withinbetween about 3.38% and about 4.12% w/w. Thus, in accordance with thepresent invention, the amount of imiquimod recovery from preferredformulations will fall within about the 100%±10% w/w specification oftheir target concentrations.

TABLE 20 Percentage of Imiquimod that is Recovered from the Formulationsas Compared to Theoretical when the Formulations are Stored at 25° C.and 40° C. over a 6 Month Period. Highlighted Grey Areas Indicate TimePoints Which Are Not Tested Due To Rejection/Omission Of Formulations (n= 3 ± sd). T = 1 month T = 1 month T = 2 months T = 2 months Imiquimod T= 0 25° C. 40° C. 25° C. 40° C. Formulations Mean SD Mean SD Mean SDMean SD Mean SD Aldara ® 5% 100.38 ± 0.25 100.60 ± 0.10 100.41 ± 0.04100.58 ± 0.10 101.40 ± 0.29 3M 257 (1%) 100.29 ± 0.12 104.36 ± 0.18104.98 ± 2.41 102.31 ± 0.46 102.42 ± 0.10 197 96.81 ± 0.17 97.74 ± 0.2099.22 ± 0.33 99.28 ± 0.14 101.47 ± 0.22 183 97.69 ± 0.21 99.73 ± 0.3299.43 ± 2.77 99.61 ± 0.33 100.01 ± 0.05 245 182 96.76 ± 0.25 102.01 ±0.01 98.46 ± 0.15 99.00 ± 0.12 98.07 ± 0.10 189 98.73 ± 0.19 100.72 ±0.17 99.20 ± 0.25 184 100.09 ± 0.08 101.71 ± 0.14 96.86 ± 0.20 193 188100.28 ± 0.02 99.39 ± 0.17 97.04 ± 0.21 195 99.39 ± 0.32 99.33 ± 0.0797.84 ± 0.25 101.13 ± 0.10 103.13 ± 0.10 255 98.87 ± 0.42 100.67 ± 0.0298.73 ± 0.13 256 97.58 ± 0.03 100.06 ± 0.22 98.05 ± 0.12 99.74 ± 0.0799.28 ± 0.24 Graceway 98.62 ± 0.11 102.32 ± 0.28 96.66 ± 0.18 101.65 ±0.06 101.02 ± 0.10 Aldara ® 5% Imiquimod 110 101.06 ± 0.35 102.17 ± 0.9599.48 ± 0.19 101.46 ± 0.09 99.03 ± 0.14 116 98.63 ± 0.25 99.15 ± 0.1396.87 ± 0.09 117 99.00 ± 0.73 102.06 ± 0.10 98.42 ± 0.09 250 97.67 ±0.11 101.88 ± 0.06 99.37 ± 1.05 99.43 ± 0.20 99.74 ± 0.13 254 96.29 ±0.27 99.75 ± 0.09 97.11 ± 0.25 120 99.79 ± 0.27 100.61 ± 0.03 98.82 ±0.17 121 235 99.25 ± 0.25 102.80 ± 0.20 100.78 ± 0.11 123 99.71 ± 0.17101.49 ± 0.10 99.52 ± 0.34 102.08 ± 0.34 101.11 ± 0.27 124 93.17 ± 0.0794.26 ± 0.04 92.93 ± 0.14 125 98.37 ± 0.23 102.33 ± 0.29 99.14 ± 0.1499.99 ± 0.21 100.38 ± 0.09 126 102.37 ± 0.58 102.84 ± 0.45 104.11 ± 0.04100.02 ± 0.95 101.32 ± 0.40 Pbo4 0 ± 0 0 ± 0 0 ± 0 0 ± 0 0 ± 0 Pbo1 0 ±0 0 ± 0 0 ± 0 0 ± 0 0 ± 0 Pbo2 0 ± 0 0 ± 0 0 ± 0 0 ± 0 0 ± 0 Pbo3 0 ± 00 ± 0 0 ± 0 0 ± 0 0 ± 0 T = 3 month T = 3 month T = 6 month T = 6 monthImiquimod 25° C. 40° C. 25° C. 40° C. Formulations Mean SD Mean SD MeanSD Mean SD Aldara ® 5% 104.12 ± 0.23 104.12 ± 0.79 106.78 ± 4.64 105.41± 0.60 3M 257 (1%) 103.16 ± 0.37 105.79 ± 0.27 107.09 ± 1.63 103.76 ±3.59 197 102.69 ± 0.92 102.69 ± 0.92 100.39 ± 1.04 101.11 ± 2.66 183100.80 ± 1.07 103.70 ± 1.58 100.75 ± 1.82 102.19 ± 1.33 245 182 101.48 ±0.27 104.39 ± 1.55 102.91 ± 1.16 99.21 ± 4.25 189 184 193 188 195 103.00± 0.15 106.25 ± 0.99 106.84 ± 1.38 106.28 ± 1.22 255 256 101.74 ± 0.37101.71 ± 0.44 105.42 ± 2.10 105.55 ± 3.20 Graceway 103.58 ± 0.19 103.64± 0.15 101.70 ± 0.79 103.20 ± 1.85 Aldara ® 5% Imiquimod 110 102.73 ±0.64 103.36 ± 0.38 102.42 ± 1.16 102.38 ± 2.82* 116 117 250 101.57 ±0.35 105.32 ± 2.42 102.45 ± 0.50 101.14 ± 2.23 254 120 121 235 123103.27 ± 0.31 102.35 ± 0.47 105.49 ± 1.11 103.34 ± 1.44 124 125 103.28 ±0.76 104.87 ± 2.65 102.48 ± 1.27 103.87 ± 1.37 126 99.28 ± 3.25 98.43 ±0.55 101.95 ± 0.37 103.02 ± 1.89 Pbo4 0 ± 0 0 ± 0 0 ± 0 0 ± 0 Pbo1 0 ± 00 ± 0 0 ± 0 0 ± 0 Pbo2 0 ± 0 0 ± 0 0 ± 0 0 ± 0 Pbo3 0 ± 0 0 ± 0 0 ± 0 0± 0 *30° C. sample analysed, as 40° C. had shown signs of phaseseparation.

2. Stability of Benzyl Alcohol in Formulations

In Table 21, Benzyl alcohol content is found to fall over the durationof the stability tests. The greatest loss observed is in the placebo's;Pbo4 (1.08±0.02% w/w), Pbo1 (1.01±0.03% w/w), Pbo2 (1.04±0.08% w/w) andPbo3 (1.11±0.00% w/w) and the active formulation 257 (1%) (1.37±0.01%w/w) which shows a loss in benzyl alcohol at about 40° C. for about 6months down from 2.0% w/w. The specified range for benzyl alcohol in theAldara® 5% imiquimod cream formulations (1.0 to 2.1% w/w), are withinspecification for Aldara® 5% imiquimod cream. The decrease in benzylalcohol content from the formulations is possibly the result of theformation of an ester (benzyl isostearate), whereby there is a reactionbetween the excipients of benzyl alcohol and isostearic acid.

TABLE 21 Amount of Benzyl Alcohol that is Recovered from theFormulations when the formulations that are Stored at 25° C. and 40° C.over a 6 Month Period. Highlighted Grey Areas Indicate Time Points WhichAre Not Tested Due To Rejection/Omission Of Formulations (N = 3 ± Sd). T= 1 month T = 1 month T = 2 months T = 2 months Imiquimod T = 0 25° C.40° C. 25° C. 40° C. Formulations Mean SD Mean SD Mean SD Mean SD MeanSD Aldara ® 5% 3M 2.11 ± 0.02 2.04 ± 0.01 1.86 ± 0.01 2.04 ± 0.01 1.84 ±0.06 257 (1%) 2.06 ± 0.01 2.01 ± 0.01 1.74 ± 0.02 2.00 ± 0.04 1.07 ±0.03 197 2.06 ± 0.00 2.06 ± 0.01 1.86 ± 0.01 2.05 ± 0.00 1.91 ± 0.02 1832.05 ± 0.01 2.01 ± 0.01 1.85 ± 0.12 2.00 ± 0.01 1.81 ± 0.00 245 182 2.17± 0.00 2.17 ± 0.00 1.95 ± 0.01 2.11 ± 0.04 1.97 ± 0.00 189 2.11 ± 0.012.06 ± 0.02 1.88 ± 0.02 184 2.13 ± 0.01 2.09 ± 0.01 1.86 ± 0.01 193 1882.15 ± 0.02 2.05 ± 0.02 1.84 ± 0.01 195 2.12 ± 0.02 2.04 ± 0.01 1.85 ±0.02 2.07 ± 0.03 1.95 ± 0.03 255 2.09 ± 0.01 2.04 ± 0.00 1.81 ± 0.02 2562.07 ± 0.01 2.05 ± 0.00 1.85 ± 0.00 2.06 ± 0.02 1.87 ± 0.03 GracewayAldara ® 2.06 ± 0.01 2.06 ± 0.00 1.80 ± 0.00 2.05 ± 0.00 1.91 ± 0.02 5%Imiquimod 110 2.09 ± 0.01 2.04 ± 0.01 1.84 ± 0.01 2.04 ± 0.02 1.91 ±0.02 116 2.08 ± 0.01 2.05 ± 0.01 1.87 ± 0.01 117 2.11 ± 0.01 2.06 ± 0.011.82 ± 0.05 250 2.03 ± 0.01 2.00 ± 0.01 1.78 ± 0.07 1.96 ± 0.02 1.70 ±0.01 254 2.07 ± 0.01 2.04 ± 0.01 1.89 ± 0.01 120 2.11 ± 0.00 2.00 ± 0.011.77 ± 0.02 121 235 2.10 ± 0.00 2.10 ± 0.02 1.92 ± 0.02 123 2.11 ± 0.012.05 ± 0.00 1.82 ± 0.01 2.06 ± 0.01 1.85 ± 0.01 124 1.96 ± 0.01 1.89 ±0.01 1.71 ± 0.00 125 2.08 ± 0.01 2.06 ± 0.01 1.82 ± 0.00 2.02 ± 0.011.82 ± 0.01 126 2.00 ± 0.02 2.02 ± 0.01 1.89 ± 0.01 1.86 ± 0.02 1.65 ±0.02 PBO4 1.93 ± 0.02 1.83 ± 0.08 1.90 ± 0.03 1.91 ± 0.01 1.53 ± 0.00PBO1 1.82 ± 0.01 1.65 ± 0.00 1.85 ± 0.09 1.54 ± 0.10 PBO2 1.83 ± 0.011.65 ± 0.01 1.87 ± 0.19 1.70 ± 0.09 PBO3 1.97 ± 0.00 1.81 ± 0.01 2.09 ±0.00 1.81 ± 0.00 T = 3 month T = 3 month T = 6 month T = 6 monthImiquimod 25° C. 40° C. 25° C. 40° C. Formulations Mean SD Mean SD MeanSD Mean SD Aldara ® 5% 3M 1.88 ± 0.02 1.67 ± 0.02 1.76 ± 0.05 1.41 ±0.00 257 (1%) 1.74 ± 0.01 1.37 ± 0.01 1.58 ± 0.01 1.02 ± 0.08 197 1.85 ±0.01 1.70 ± 0.02 1.74 ± 0.05 1.47 ± 0.02 183 1.78 ± 0.01 1.56 ± 0.021.66 ± 0.04 1.24 ± 0.01 245 182 1.94 ± 0.01 1.82 ± 0.04 1.85 ± 0.03 1.48± 0.05 189 184 193 188 195 1.88 ± 0.01 1.74 ± 0.02 1.80 ± 0.01 1.48 ±0.01 255 256 1.84 ± 0.01 1.88 1.68 0.01 1.76 ± 0.01 1.46 ± 0.01 GracewayAldara ® 1.87 ± 0.02 1.65 ± 0.01 1.73 ± 0.00 1.38 ± 0.03 5% Imiquimod110 1.87 ± 0.02 1.75 ± 0.01 1.78 ± 0.04 1.72 ± 0.02 116 117 250 1.74 ±0.01 1.47 ± 0.03 1.59 ± 0.02 1.12 ± 0.02 254 120 121 235 123 1.84 ± 0.011.59 ± 0.00 1.73 ± 0.02 1.34 ± 0.01 124 125 1.85 ± 0.00 1.63 ± 0.04 1.73± 0.02 1.32 ± 0.02 126 2.00 ± 0.04 1.70 ± 0.04 2.01 ± 0.03 1.55 ± 0.02PBO4 1.81 ± 0.01 1.39 ± 0.01 1.71 ± 0.01 1.08 ± 0.02 PBO1 1.93 ± 0.031.55 ± 0.04 1.58 ± 0.02 1.01 ± 0.03 PBO2 2.01 ± 0.13 1.61 ± 0.08 1.65 ±0.05 1.04 ± 0.08 PBO3 2.12 ± 0.04 1.70 ± 0.00 1.73 ± 0.01 1.11 ± 0.00*30° C. sample analysed, as 40° C. had shown signs of phase separation

(D) Microscopic Stability of the Formulations

In Table 22, there is no change in the particle size in any of theformulations tested at about 25° C. over about a 6 month period. Inaddition, and with reference to the microscopic photographs presented inFIGS. 63A-C and 64; no crystals are detected. For completeness andreference, the pictures of the formulations rejected after one monthstability are shown in FIGS. 65A-B.

TABLE 22 Results of Particle Size of the Formulations when viewed undera Microscope at 25° C. over a 6 Month Period. Particle size (μM) t = t =t = Formulation T = 0 t = 1 Month 2 Months 3 Months 6 Months 3M <10 <10<10 <10 <10 Aldara ® 5% GRACEWAY <10 <10 <10 <10 <10 Aldara ® 5% 257(1%) <10 <10 <10 <10 <10 110 <10 <10 <10 <10 <10 250 <10 <10 <10 <10 <10182 <10 <10 <10 <10 <10 195 10 10 10 10 10 123 10 10 10 10 10 125 10 1010 10 10 256 10 10 10 10 10 197 10 10 10 10 10 183 10 10 10 10 10 126<10 <10 <10 <10 <10 Pbo1 <10 <10 <10 <10 <10 Pbo2 <10 <10 <10 <10 <10Pbo3 <10 <10 <10 <10 <10 Pbo4 <10 <10 <10 <10 <10

(E) Macroscopic Stability of the Formulations

In Table 23, there are no obvious physical changes in the formulationsthat are tested over the six month stability program, with the exceptionof the placebos, which become notably less viscous. See also Tables24-26.

TABLE 23 Macroscopic Appearance when Imiquimod Formulations are storedat about 25° C. over about a 6 Month Period. Appearance spatula Test(25° C. sample only) Visual Viscosity (25° C. sample only) Imiquimod t =1 t = 2 t = 3 t = 6 t = 1 t = 2 t = 3 t = 6 Formulation t = 0 monthmonths months months t = 0 month months months months 3M Glossy, Glossy,Glossy, Glossy, Glossy, High Medium- Medium Medium- Medium Aldara ® veryvery very very very High High 5% smooth smooth smooth smooth smoothImiquimod Graceway Glossy, Glossy, Glossy, Glossy, Glossy, High HighMedium- High Medium Aldara ® very very very very very High 5% smoothsmooth smooth smooth smooth Imiquimod 257 (1%) Glossy Glossy Glossy,Glossy, Glossy, Medium Medium- Medium- Medium- Low and and very veryvery High High High viscosity smooth smooth smooth smooth smooth 110Glossy, Glossy, Glossy, Glossy, Glossy, High High High High Medium veryvery slightly slightly slightly slightly slightly textured texturedtextured textured textured 250 Glossy Glossy Glossy, Glossy, Glossy,Medium Medium- Medium- Medium- Medium and and Very Very Very High HighHigh smooth, textured slightly slightly slightly some textured texturedtextured aeration 182 Very Very Very Very Very High Medium- Medium-Medium- High glossy glossy glossy glossy glossy High High High and andand and and smooth smooth smooth smooth smooth 195 Glossy, Glossy,Glossy, Glossy, Glossy, High High Medium- Medium- High slightly slightlyvery slightly slightly High High textured textured slightly texturedtextured textured 123 Glossy Glossy, Glossy, Glossy, Glossy, Medium-Medium- Medium- High Medium and slightly slightly slightly slightly HighHigh High smooth textured textured, textured, textured smoothed smoothedout out 124 Glossy Glossy Glossy, Glossy, Glossy, Medium Medium MediumMedium- Low and and smooth smooth slightly High smooth smooth withtextured slight aeration 256 Glossy, Glossy, Glossy, Glossy, Glossy,Medium- Medium- Medium- Medium- High slightly slightly slightly slightlyslightly High High High High textured textured textured texturedtextured 197 Glossy, Glossy, Glossy Glossy Glossy Medium Medium- HighHigh High slightly very and and and High textured slightly texturedslightly slightly textured textured textured 183 Glossy, Glossy GlossyGlossy Glossy High Medium- Medium- Medium- Low smooth and and and andHigh High High slight smooth smooth smooth smooth aeration 126 Glossy,Smooth, Glossy Slightly Glossy Medium Medium Medium Medium Low veryslightly and textured, viscosity slightly textured, smooth sheentextured glossy Pbo1 Glossy Very Very Very Glossy Low Medium- Medium-Low Low and glossy glossy glossy and Low Low smooth and and and smoothsmooth smooth smooth Pbo2 Glossy Glossy Glossy Glossy, Glossy Medium-Medium Medium- Medium- Low and and and very and Low Low Low smoothsmooth smooth slightly smooth textured Pbo3 Glossy Glossy Glossy,Glossy, Glossy Low Medium- Medium- Medium- Medium and and very very andLow Low Low smooth smooth slightly slightly smooth textured textured butbut smoothed smoothed out out Pbo4 Glossy Glossy Glossy Glossy SmoothMedium- Medium Medium- Low Low and and and and cream Low Low smoothsmooth smooth smooth high sheen

TABLE 24 Stability Data for 10 Formulations, i.e., Formulations 116,117, 120, 124, 188, 184, 189, 235, 254 and 255, rejected after 1 MonthStability, with respect to the Spatula Test, Visual Viscosity andParticle Size (as determined by microscopy). Majority of particle sizeSpatula Test Visual Viscosity (μM) Formu- T = 1 T = 1 T = 1 lation T = 0Month T = 0 Month T = 0 Month 116 Glossy, Glossy, Medium Medium- 10 10textured textured High 117 Glossy, Glossy, Medium- Medium- <10 <10slightly slightly High High textured textured 254 Smooth Smooth, HighMedium- <10 <10 with matt matt High appearance 120 Smooth, Smooth, VeryHigh Very High <10 <10 matt matt appearance, some aeration 235 Glossy,Glossy, Medium- Medium <50 <50 textured but very Low does slightlysmooth out textured but does smooth out 188 Glossy and Glossy Medium-High <10 <10 textured and Low textured 189 Glossy, Glossy, High VeryHigh <10 <10 very slightly slightly textured textured 184 Glossy,Glossy, High High <10 <10 slightly slightly textured textured 255 Glossyand Glossy High High 10 <10 smooth and smooth 124 Glossy, Glossy,Medium- Medium- <10 <10 very very High High slightly slightly texturedtextured

TABLE 25 pH Stability Data for 10 Imiquimod Formulations, i.e.,Formulations 116, 117, 120, 124, 188, 184, 189, 235, 254 and 255,Rejected after 1 Month Stability. Formulation pH Identity T = 0 T = 1Month 116 5.0 4.7 117 4.5 4.5 254 4.7 4.7 120 4.5 4.5 235 4.5 4.5 1884.7 4.7 189 4.7 4.7 184 4.7 4.7 255 4.5 4.5 124 4.5 4.5

TABLE 26 Viscosity Stability Data for 10 Imiquimod Formulations, i.e.,Formulations 116, 117, 120, 124, 188, 184, 189, 235, 254 and 255,Rejected after 1 Month Stability Bohlin Viscosity For- Brookfield (cps)(cps) mulation Crossover G′ T = 1 T = 1 Identity T = 0 T = 0 T = 0 MonthT = 0 Month 116 9.0 478 601867 63500 15350 13300 117 14.0 1151 12166671281000 17250 15600 254 10.3 1399 1476667 1423000 19050 19000 120 15.3884 1416667 1393000 20250 20900 235 6.0 134 245333 313000 6350 5700 18814.0 708 1141333 1254000 20350 20750 189 34.8 1037 1344333 1463000 1870018550 184 23.0 1054 1475667 1350000 20200 21600 255 16.0 1488 24833331334000 21150 25150 124 7.0 561 849000 663000 14400 14250

(F) Brookfield Viscosity Stability Results of Formulations

In Table 27, Brookfield viscosity measurements are notoriously variableand, as such, there are fluctuations in the measurements of theformulations over about a 6 month period when stored at about 25° C.Variations in results are further observed if the spindle or the speedof the spindle rotation is altered. Although the majority of theformulations are measured using the same settings and spindle; theplacebo formulations (Pbo1, Pbo2, Pbo3 and Pbo4) result in torquemeasurements below the threshold required for accurate measurements andsubsequently readings are inaccurate. Attempts are made to change thesettings and spindles; however, results are vastly different and thusunreliable. See also Tables 24-26.

TABLE 27 Viscosity and Rheology Measurements of Imiquimod Formulationsstored at 25° C. over a 6 Month Period. Bohlin Viscosity (cPs)Brookfield (cPs) (based on 3M method) Formulation G(Pa) Crossover (o) t= 1 t = 2 t = 3 t = 6 t = 1 t = 2 t = 3 t = 6 Identity t = 0 t = 0 t = 0Month Months Months Months t = 0 Month Months Months Months 3M 507 12.5660333 623000 337000 428833 166233 15700 17300 17600 13296 12833Aldara ® 5% Imiquimod Graceay 716 10.5 1108667 1109000 587667 768566252033 18250 20250 19900 18697 15100 Aldara ® 5% Imiquimod 257 (1%) 35210.52 642667 600000 220333 351566 * 13600 15050 11500 6075 3139 110 78211.5 87100 119000 782333 619300 366067 16250 16400 18000 16368 14076 250320 9 695333 816000 557333 394166 141400 13700 16400 14950 10587 5890182 702 8.5 693067 1097000 904667 523033 273233 18050 17850 18550 1682013691 195 692 15 1141333 1293000 779333 618133 381700 17000 17600 1650016208 14696 123 510 10.8 804000 773000 386333 701500 199933 15800 1625015200 13095 9587 125 485 8.5 603000 707000 429667 412133 127067 1490017050 15300 12069 8301 256 667 7.3 1126000 958000 697667 757523 24950019400 18300 18750 15453 12379 197 646 14 1082667 1377000 613667 607366274400 17750 17850 17600 15861 13524 183 719 10.3 693333 839000 596000332900 188000 18700 19100 18600 15906 12120 126 AP .. 430100 235066228104 212500 105720 16783 12739 14749 10856.5 8789.5 PBO1 306 1185000 * • * * 12100 14450 7500 7969 2508.3 PBO2 263 13 79500 . . 1420013950 9100 6452.5 2617.6 PBO3 305 11.5 117000 12200 13850 9000 83953256.5 PBO4 227800 • 10350 7953 5511 3550 2247 • results un-reliable andnot presented as the torque was out of range (due to low viscosity) forthe Brookfield viscometer using the settings and spindle used for allthe other samples. Alternative spindles and settings were investigated;however, the results were vastly different than previous readings. ** norecorded measurements, as test was only required for initialformulations choice and development.

(G) Bohlin Viscosity Results

Also as shown in Table 27, the Bohlin viscosity results are in contrastto the results of the Brookfield viscosity and appear to be moreconsistent for all formulations. A fall in the viscosity is observed for257 (1%) and placebo formulations, Pbo1-4, over the 6 month stabilitystudy, whereby the viscosity falls by approximately 50%. Allformulations are within the range of the specifications for the Aldara®5% imiquimod cream formulation (2000 to 35,000 cps). See also Tables24-26.

(H) pH Stability of Formulations

In Table 28, it reports that the specification for all formulations thatare tested, fall within the Aldara® 5% imiquimod cream specifications(pH 4.0 to 5.5). A slight variation in pH is observed over the 6 monthperiod for all of the formulations. See also Tables 24-26.

TABLE 28 ph for Imiquimod Formulations when Stored at about 25° C. andabout 40° C. over a 6 Month Period. Grey Areas Indicate No Test IsPerformed. pH t = 0 t = 1 month t = 2 months t = 3 months t = 6 monthsFormulation 25° C. 25° C. 40° C. 25° C. 40° C. 25° C. 40° C. 25° C. 40°C. 3M Aldara ® 4.5 4.5 4.5 4.5 4.5 4.7 4.3 4.1 5% Imiquimod Graceway 4.54.5 4.5 4.5 4.5 4.5 4.3 4.5 Aldara ® 5% Imiquimod 257 (1%) 4.2 4.5 4.54.5 4.5 4.1 4.1 3.9 110 5 4.7 4.7 4.7 4.7 4.4 4.5 4.3* 250 4.2 4.2 4.24.5 4.2 4 4.2 4.1 182 4.5 4.5 4.5 4.5 4.5 4.6 4.3 4.3 195 4.7 4.5 4.54.5 4.5 4.7 4.5 4.5 123 4.5 4.7 4.7 4.7 4.7 4.3 4.1 4.3 125 4.5 4.5 4.54.5 4.5 4.2 4.1 4.1 256 4.7 4.7 4.7 4.7 4.7 4.4 4.3 4.3 197 4.5 4.7 4.74.7 4.7 4.6 4.5 4.3 183 4.5 4.5 4.5 4.5 4.5 4.2 4.5 4.1 126 4.2 4.3 4.34.3 4.3 4.3 4.3 4.1 4.1 Pbo1 4.5 4.5 4.5 4.5 4.2 4.5 4.0 4.0 Pbo2 4.54.5 4.2 4.2 4.2 4.2 4.1 4.1 Pbo3 4.5 4.5 4.5 4.2 4.2 4.2 4.2 4.2 Pbo44.5 4.2 4.5 4.2 4.2 4.1 4.1 4.0 4.0 *30° C. sample analyzed as the 40°C. sample had phase separated

(I) Preservative Efficacy Test

Table 29 reports final viable counts of organism inoculations that areadded to the formulations.

TABLE 29 Total Viable Counts that are obtained for the OrganismInoculates into the Imiquimod Formulations Mimi for 182 Cfu/ml for 126Organism and 110 and Pbo4 Staphylococcus aureus 2.4E+08 3.1E+08Escherichia coli 1.7E+08 2.1E+08 Pseudomonas aeruginosa 9.0E+07 1.1E+08Candida albicans 1.0E+08 1.1E+08 Aspergillus niger 1.7E+07 1.6E+08

Table 30 shows colony forming unit count (cfu) for Staphylococcus aureusafter PET validation is performed on two formulations stored at about2-8° C.

TABLE 30 Viable counts that are obtained for Staphylococcus aureus thatare Inoculated Formulations after PET Validation Imiquimod ViableFormulation Suspension fluid Dilution count (cfu/ml) 110 D/E broth 1 mlin 9 ml 2.20E+08 0.1 ml in 0.9 ml 2.80E+08 Ringer's solution 1 ml in 9ml 1.00E+03 0.1 ml in 0.9 ml 1.50E+03 182 D/E broth 1 ml in 9 ml2.30E+08 0.1 ml in 0.9 ml 2.60E+08 Ringer's solution 1 ml in 9 ml1.00E+03 0.1 ml in 0.9 ml 1.40E+03

The preservative efficacy test (“PET”) is a procedure used todemonstrate antimicrobial activity of a formulation with respect to thepreservative system used. In Table 31, cell counts that are recoveredfrom the inoculated formulations at various time points are reported.The data shows that sufficient log reductions are present in theformulations at about 2-8° C. and about 40° C. and meet the requirementsthat are specified in both the USP and EP.

TABLE 31 Colony Forming Unit Counts that are recovered (Cfu/Ml) for EachOrganism from the Imiquimod Formulations, over 28 Days Organismsrecovered-(cfu/ml) Pass/ Formulation Organism 0 h 24 h 48 h 7 days 19days 21 days 28 days Fail Pbo4 S. aureus 3.10E+05 0.00E+00 0.00E+000.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS STORAGE: E. coil 5.00E+030.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS 2-8° C. Ps.aeruginosa 9.00E+03 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+000.00E+00 PASS Va albicans 5.00E+04 1.80E+03 0.00E+00 0.00E+00 0.00E+000.00E+00 0.00E+00 PASS A. niger 1.60E+05 6.00E+03 2.50E+03 0.00E+000.00E+00 0.00E+00 0.00E+00 PASS Pbo4 S. aureus 1.70E+06 0.00E+000.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS STORAGE: 40° C. E.coil 6.00E+03 0.00E+00 G.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 PASSPs. aeruginosa 1.30E+04 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+000.00E+00 PASS C. albicans 2.60E+04 4.10E+03 1.30E+03 0.00E+00 0.00E+000.00E+00 0.00E+00 PASS A. niger 3.00E+05 1.70E+04 3.30E+03 0.00E+000.00E+00 0.00E+00 0.00E+00 PASS 126 S. aureus 5.70E+04 0.00E+00 0.00E+000.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS STORAGE: E. coil 1.20E+060.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS 2-8° C. Ps.aeruginosa 1.40E+04 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+000.00E+00 PASS C. albicans 3.50E+04 5.00E+03 4.00E+02 0.00E+00 0.00E+000.00E+00 0.00E+00 PASS A. niger 1.00E+05 2.10E+04 2.50E+03 0.00E+000.00E+00 0.00E+00 0.00E+00 PASS 126 S. aureus 2.10E+04 0.00E+00 0.00E+000.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS STORAGE: 40° C. E. coil5.00E+05 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS Ps.aeruginosa 1.50E+04 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+000.00E+00 PASS C-albicans 3.80E+04 3.60E+03 2.50E+03 0.00E+00 0.00E+000.00E+00 0.00E+00 PASS A. niger 1.00E+05 2.90E+03 1.60E+03 0.00E+000.00E+00 0.00E+00 0.00E+00 PASS 110 S. aureus 1.00E+06 0.00E+00 0.00E+000.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS STORAGE: E. coli 7.00E+050.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS 2-FPG Ps.aeruginosa 8.00E+04 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+000.00E+00 PASS C. albicans 8.00E+05 2.60E+04 7.00E+03 7.00E+01 0.00E+000.00E+00 0.00E+00 PASS A. niger 6.00E+04 9.00E+04 2.30E+04 7.00E+033.70E+02 0.00E+00 0.00E+00 PASS 110 S. aureus 6.00E+05 0.00E+00 0.00E+000.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS STORAGE: 40° C. E. coil8.00E+04 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS Ps.aeruginosa 7.00E+05 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+000.00E+00 PASS C. albicans 1.60E+05 1.50E+04 4.00E+03 2.20E+02 0.00E+000.00E+00 0.00E+00 PASS A. niger 7.00E+04 6.00E+04 2.50E+04 1.90E+041.90E+02 0.00E+00 0.00E+00 PASS 182 S. aureus 1.70E+06 0.00E+00 0.00E+000.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS STORAGE: E coli 1.70E+060.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS 2-8° C. Ps.aeruginosa 7.00E+05 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+000.00E+00 PASS C. albicans 3.00E+05 2.10E+04 1.90E+03 3.00E+03 0.00E+000.00E+00 0.00E+00 PASS A niger 4.00E+05 5.00E+03 2.40E+03 3.00E+030.00E+00 0.00E+00 0.00E+00 PASS 182 S. aureus 1.50E+06 0.00E+000.00E+130 0.00E+00 0.00E+00 0.00E+00 0.00E+00 PASS STORAGE: 40° C. E.coil 1.10E+06 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 PASSPs. aeruginosa 6.00E+05 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+000.00E+OG PASS C. albicans 7.00E+05 3.00E+04 3.00E+03 7.00E+03 0.00E+000.00E+00 0.00E+00 PASS A. niger 7.00E+05 6.00E+03 2.70E+03 1.70E+031.20E+02 0.00E+00 0.00E+00 PASS

(J) Test Item Release Studies Through Synthetic Membranes

In FIG. 58, it indicates that there is a trend between theconcentrations of imiquimod present in the formulation as compared tothe amount that is released. This is supported by the results presentedin FIG. 59 and the corresponding statistical analysis, where it can beseen that that the higher the imiquimod concentration in theformulation, the greater the release of imiquimod. However, formulation183 (3.75% w/w imiquimod) gives a statistically (at a 95% confidencelevel) greater cumulative release of imiquimod when it is compared tothe 2.5% w/w formulations. All of the 5% w/w formulations, i.e., Aldara®5% imiquimod cream batch, Aldara® 5% imiquimod cream Graceway batch, andAldara® 5% imiquimod cream Sachet), result in significantly (p<0.05)higher amounts of imiquimod released over a 3 h time period incomparison to 1%, 2.5% and 3.75% w/w imiquimod formulations. There is nostatistical difference (p>0.05) in the total cumulative amount ofimiquimod that is released from any of the 3.75% w/w imiquimodformulations; likewise there is also no statistical difference (p>0.05)from the 2.5% w/w imiquimod formulations.

ANOVA statistical analysis (95% confidence level): mean total cumulativeamount that is released (μg/cm²) after 3 h (from results that arepresented in FIG. 58):

Source DF SS MS F P Formulation 12 86439222 7203268 19.40 0.000 Error 3914484370 371394 Total 51 100923592 Individual 95% CIs For Mean Based onPooled StDev Level N Mean St. Dev

Aldara 3M 5% 4 5332.8 734.2

Aldara sachet 4 4605.5 626.9

110 4 1862.8 185.9

250 4 1845.6 206.4

182 4 3161.3 774.9

195 4 3046.2 988.2

123 4 2094.9 674.6

125 4 2134.1 369.0

256 4 2918.7 59.5

197 4 2766.0 929.1

183 4 3453.2 564.4

MedPharm Aldara 4 4813.3 660.7

257% 4 586.9 170.2

S = 609.4 R-Sq = 85.65% R-Sq (adj) = 81.23% Pooled StDev = 609.4

ANOVA statistical analysis (95% confidence level): mean total cumulativeamount that is released (μg/cm²) after 3 h for each concentration ofimiquimod in the formulations that are tested (from results that arepresented in FIG. 59):

Source DF SS MS F P Formulation 3 83957708 27985903 79.18 0.000 Error 4816965878 353456 Total 51 100923586 Individual 95% CIs For Mean Based onPooled StDev Level N Mean St. Dev

1% 4 586.9 170.2

2.50% 16 1984.4 389.9

3.75% 20 3069.1 702.3

5.00% 12 4917.2 689.4

S = 594.5 R-Sq = 83.19% R-Sq (adj) = 82.14% Pooled StDev = 594.5

The result for the rate of release presented in Table 32, indicate thatthe higher the amount of imiquimod in the formulation, the faster therate of release of imiquimod. Similar to the results of the cumulativeamount permeated, there is no statistical difference (p>0.05) betweenthe results for the 2.5% w/w imiquimod formulations (Table 32 and FIG.67) and likewise for the 3.75% w/w imiquimod formulations (Table 32 andFIG. 68). See also FIGS. 66 and 69.

TABLE 32 Comparison of Mean Flux of Imiquimod (μg/Cm²) over a 3 H Periodfor Membrane Release Tests (Mean ± Sd, Where N = 4) that are Presentedas a Function of √Time from 15 Min To 3 H. Flux √time Formulations Mean± sd Graceway Aldara ® 5% 3720.65 ± 569.38 Imiquimod 3M Aldara ® 5%Imiquimod 3873.38 ± 479.64 Cream Bulk 3M Aldara ® 5% Imiquimod 3319.56 ±494.32 Cream sachet 257 (1%)  504.40 ± 148.43 123 (2.5%) 1539.39 ±482.36 250 (2.5%) 1396.68 ± 173.65 125 (2.5%) 1592.98 ± 324.51 110(2.5%) 1518.29 ± 151.17 182 (3.75%) 2410.03 ± 599.08 195 (3.75%) 2310.06± 597.59 256 (3.75%) 2424.87 ± 28.09  197 (3.75%) 2116.53 ± 723.60 183(3.75%) 2516.84 ± 357.41

ANOVA statistical analysis (95% confidence level): mean amount ofimiquimod released (μg/cm²) over a 3 hour period for the membranerelease studies (mean±sd, where n=4) presented as a function of √timefrom 15 min to 3 h (from results presented in Table 32):

Source DF SS MS F P Formulation 12 45353042 3779420 19.05 0.000 Error 397739267 198443 Total 51 53092309     Level     N     Mean     St. DevIndividual 95% CIs For Mean Based on Pooled StDev

3M Aldara ® 5% Imiquimod Cream Bulk 4 3873.4 479.6

3M Aldara ® 5% Imiquimod Cream Sachet 4 3319.6 494.3

110 4 1518.3 151.2

250 4 1396.7 173.6

182 4 2410.0 599.1

195 4 2310.1 597.6

123 4 1539.4 482.4

125 4 1593.0 324.5

256 4 2424.9 28.1

197 4 2116.5 723.6

183 4 2516.8 357.4

Graceway ® 5% Imiquimod Cream 4 3720.6 569.4

257 1% 4 504.4 148.4

S = 445.5 R-Sq = 85.42% R-Sq (adj) = 80.94% Pooled StDev = 445.5

ANOVA statistical analysis (95% confidence level): Comparison of themean amount of imiguimod released (μg/cm²) over a 3 hour period for the3M Aldara® 5% imiquimod cream lkg batch, the 3M Aldara® 5% imiquimodcream sachet, the Graceway Aldara® 5% imiquimod cream 1 kg batch and257, 1% Imiquimod formulation (mean±sd, where n=4)—refer to FIG. 66:

Source DF SS MS F P Formulation  3 57378855 19126285 54.74 0.000 Error12  4192460  349372 Total 15 61571315     Level     N     Mean     St.Dev Individual 95% CIs For Mean Based on Pooled StDev

Aldara 3M 5% 4 5332.8 734.2

Aldara sachet 4 4605.5 626.9

MedPharm Aldara 4 4813.3 660.7

U2F 1% 4 586.9 170.2

S = 591.1 R-Sq = 93.19% R-Sq (adj) = 91.49% Pooled StDev = 591.1

ANOVA statistical analysis (95% confidence level): Comparison of themean amount of imiquimod released (μg/cm²) over a 3 hour period for 2.5%imiquimod formulations 123, 250, 125 and 110 (mean±sd, where n=4)—referto FIG. 67:

Source DF SS MS F P Formulation 3 274778 91593 0.55 0.659 Error 122004990 167083 Total 15 2279769     Level     N     Mean     St. DevIndividual 95% CIs For Mean Based on Pooled StDev

GW002 4 1862.8 185.9

GW008 4 1845.6 206.4

GW037 4 2094.9 674.6

GW039 4 2134.1 369.0

S = 408.8 R-Sq = 12.05% R-Sq (adj) = 0.00% Pooled StDev = 408.8

ANOVA statistical analysis (95% confidence level): Comparison of themean amount of imiquimod released (μg/cm²) over a 3 hour period for3.75% imiquimod formulations 182, 195, 256, 197 and 183 (mean±sd, wheren=4)—refer to FIG. 68:

Source DF SS MS F P Formulation  4 1084063 271016 0.49 0.743 Error 158286917 552461 Total 19 9370981     Level     N     Mean     St. DevIndividual 95% CIs For Mean Based on Pooled StDev

GW030 4 3161.3 774.9

GW033 4 3046.2 988.2

GW040 4 2918.7  59.5

GW041 4 2766.0 929.1

GW042 4 3453.2 564.4

S = 743.3 R-Sq = 11.57% R-Sq (adj) = 0.00% Pooled StDev = 743.3

As discussed under FIG. 69 in the Brief Description of the Drawings,FIG. 69 shows a comparison of the mean amount of imiguimod released(μg/cm²) over a 3 hour period for the 2.5% (▴), 3.75% (), 3M Aldara®imiquimod cream batch (

), Graceway Aldara® imiquimod cream 1 kg batch (▪) and formulation 257Imiquimod formulations (

) (mean±sd, where n=4).

Based on the results; it appears that the greater the amount ofimiquimod in the formulation, the faster and greater the total amount ofimiquimod that is released, suggesting that the amount and rate ofrelease are concentration dependant. (K) In vitro Skin Permeation Study

(1) Homogeneity

Manufacture of the formulations (about 100 g batches) is firstperformed, which batches are then mixed with the radioactive labelledmaterial. The batches are prepared by omitting about 1.38 g ofisostearic acid which is added with the radio-labelled imiquimod. Thehomogeneity of the test formulations, see Table 33, is measured asdescribed in under Homogeneity Control above and all compositions areconfirmed to meet the criterion (<10% CV).

TABLE 33 Homogeneity of Radioactivity for Imiquimod FormulationsFormulation % CV Graceway Aldara ® 5% Imiquimod Cream 0.93 3M Aldara ®5% Imiquimod Cream 1.50 182 0.80 195 2.39 256 1.17 197 0.07 183 1.54 1100.71 250 2.53 123 1.89 125 1.53 126 2.55 257 (1%) 2.30

(2) Franz Cell Study

The data that is shown in Table 34 is the actual amount of imiquimodthat is recovered for each formulation from the various matrices, whichis also represented graphically in FIG. 60. FIG. 61 represents the totalamount of imiquimod that is recovered for each formulation in theepidermis, dermis and receiver fluid combined.

TABLE 34 Amount of Imiquimod that is Recovered following Mass BalanceInvestigation Amount of imiquimod recovered ± SEM (μg) PercentageReplicates Receiver Unabsorbed Stratum Percentage total Formulationsimiquimod (n) Fluid Dose Corneum Epidermis Dermis recovered Graceway  5% 6 0.03 ±0.01 127.06 ±9.58 80.78 ±11.67 2.90 ±0.72 2.76 ±0.70 85.24±5.15 Aldara ® 5% Imiquimod Cream 3M   5% 4 0.05 0.03 132.75 ±17.6274.37 ±10.59 6.60 ±1.91 3.96 ±0.41 86.92 ±4.16 Aldara ® 5% ImiquimodCream 182 3.75% 3.75% 6 0.08 ±0.06 85.75 ±3.93 46.85 ±5.51 3.65 ±0.856.94 2.22 76.25 ±1.82 195 3.75% 3.75% 4 0.08 ±0.07 74.19 ±6.90 57.41±11.46 7.06 2.29 2.47 ±0.87 75.16 ±5.12 256 3.75% 3.75% 5 0.16 ±0.0671.73 ±7.22 33.41 ±4.77 1.99 ±0.71 9.03 ±2.37 61.91 ±3.95 197 3.75%3.75% 5 0.06 ±0.03 110.54 6.22 41.61 ±6.54 2.21 ±0.36 2.53 ±0.91 83.54±3.92 183 3.75% 3.75% 4 0.02 ±0.01 113.84 ±11.63 40.99 ±6.99 3.26 ±0.535.11 ±2.32 86.88 ±6.68 110 2.5%  2.5% 6 0.00 ±0.00 52.92 3.96 33.96±3.43 3.25 ±0.70 2.32 ±0.44 73.82 ±4.64 250 2.5%  2.5% 5 0.00 ±0.0082.46 ±2.94 28.30 ±3.67 2.35 ±0.68 1.17 ±0.30 91.25 ±3.93 123 2.5%  2.5%5 0.01 ±0.01 68.33 ±3.18 35.93 ±10.40 4.20 ±1.69 1.80 ±0.32 88.04 ±7.95125 2.5%  2.5% 6 0.02 ±0.01 72.82 ±3.92 28.88 ±4.41 1.12 ±0.42 1.52±0.42 83.32 ±2.44 126 2.5%  2.5% 5 0.01 ±0.00 64.00 ±5.27 29.59 ±4.972.36 ±0.40 4.44 ±1.62 80.15 ±6.61 257 1%   1% 4 0.01 ±0.00 28.88 ±4.6012.49 ±3.75 0.42 ±0.14 1.54 ±1.05 86.98 ±3.40

The only data rejected from that presented in Table 34, FIG. 60 and FIG.61 are obvious outliers that are observed on the basis of cell failure.

The average data for the 5%, 1%, 3.75% and 2.5% w/w formulations showingthe amount of imiquimod that is recovered from the unabsorbed fraction,in the Stratum corneum and in the epidermis, dermis and receiver fluidcombined are shown in FIG. 62. This data shows that there is a lineardose release between the amount of imiquimod applied and recovery ineach of the matrices. See also Table 35 for stability of calibrationstandards in spent receiver fluid and Tables 36-40-for statisticalanalysis.

TABLE 35 Stability of Calibration Standards in Spent Receiver Fluid(Stored In HPLC Crimp Top Vials at Each Temperature (Where Recovery wasCompared To T = 0) 48 h % recovered in Spent Standard receiver fluid(μg/ml) Spent receiver fluid: Fridge RT 37° C. 105.5 Full thickness +placebo 88.242 88.546 91.704 84.4 84.561 84.421 85.629 52.75 91.77692.027 93.779 42.2 83.976 84.144 86.439 21.1 84.584 85.162 88.000 10.5588.307 86.897 90.798 5.275 90.260 87.973 86.134 105.5 Full thickness90.545 92.275 92.278 84.4 98.841 99.790 101.010 52.75 92.317 92.15295.282 42.2 95.103 95.805 95.939 21.1 91.876 91.968 93.847 10.55 94.98993.522 97.826 5.275 94.586 95.232 90.611 105.5 Epidermal sheet + placebo83.833 84.515 84.903 84.4 95.620 96.033 98.178 52.75 85.635 88.16986.906 42.2 93.077 92.904 95.095 21.1 101.831 105.389 105.213 10.5584.046 85.095 89.945 5.275 88.881 86.540 86.828 105.5 Epidermal sheet90.465 92.089 91.501 84.4 81.350 82.276 82.694 52.75 87.669 89.09690.943 42.2 85.716 86.340 89.641 21.1 95.828 97.098 97.470 10.55 93.18094.971 97.099 5.275 88.938 91.447 85.995Tables 36-40. Statistical Analysis for Amount of Imiquimod that isRecovered following Mass Balance Test

ANOVA statistical analysis (95% confidence level): Amount of imiquimodthat is recovered following mass balance test from receiver fluid (fromresults that are presented in FIG. 60) is shown in Table 36:

TABLE 36 Source DF SS MS F P Cl 14 0.12075 0.01006 1.84 0.066 Error 520.28455 0.00547 Total 64 0.40530     Level     N     Mean     St. DevIndividual 95% CIs For Mean Based on Pooled StDev

3M Aldara ® 5% Imiquimod Cream 4 0.05250 0.05909

110 2.5% 6 0.00000 0.00000

250 2.5% 5 0.00400 0.00894

182 3.75% 6 0.07833 0.14400

195 3.75% 4 0.08250 0.14500

123 2.5% 5 0.01200 0.01095

125 2.5% 6 0.02333 0.02503

256 3.75% 5 0.15600 0.14064

197 3.75% 5 0.05800 0.06611

183 3.75% 4 0.01750 0.01708

126 5 0.00600 0.00894

Graceway Aldara ® 5% Imiquimod Cream 6 0.02833 0.03312

257 (1%) 4 0.00500 0.00577

S = 0.07397 R-Sq = 29.79% R-Sq (adj) = 13.59% Pooled StDev = 0.07397

ANOVA statistical analysis (95% confidence level): Amount of imiquimodthat is recovered following mass balance test from un-absorbed dose(from results that are presented in FIG. 60) is shown in Table 37:

TABLE 37 Source DF SS MS F P Cl 12 50777 4231 16.83 0.000 Error 52 13071251 Total 64 63848     Level     N     Mean     St. Dev Individual 95%CIs For Mean Based on Pooled StDev

3M Aldara ® 5% Imiquimod Cream 4 132.75 35.25

110 2.5% 6 52.93 9.69

250 2.5% 5 82.46 6.57

182 3.75% 6 85.75 9.63

195 3.75% 4 74.19 13.80

123 2.5% 5 68.33 7.10

125 2.5% 6 72.82 9.61

256 3.75% 5 71.73 16.15

197 3.75% 5 110.54 13.91

183 3.75% 4 113.85 23.27

126 5 63.98 11.78

Graceway Aldara ® 5% Imiquimod Cream 6 127.06 23.46

257 (1%) 4 28.88 9.20

S = 15.85 R-Sq = 79.53% R-Sq (adj) = 74.80% Pooled StDev = 15.85

ANOVA statistical analysis (95% confidence level): Amount of imiquimodthat is recovered following mass balance test from Stratum corneum (fromresults that are presented in FIG. 60) is shown in Table 38:

TABLE 38 Source DF SS MS F P Cl 12 21479 1790 6.72 0.000 Error 52 13848266 Total 64 35327     Level     N     Mean     St. Dev Individual 95%CIs For Mean Based on Pooled StDev

3M Aldara ® 5% Imiquimod Cream 4 74.38 21.17

110 2.5% 6 33.96 8.41

250 2.5% 5 28.30 8.21

182 3.75% 6 46.85 13.50

195 3.75% 4 57.41 22.92

123 2.5% 5 35.93 23.25

125 2.5% 6 28.88 10.80

256 3.75% 5 33.41 10.67

197 3.75% 5 41.61 14.62

183 3.75% 4 41.00 13.97

126 5 29.59 11.11

Graceway Aldara ® 5% Imiquimod Cream 6 80.78 28.60

257 (1%) 4 12.49 7.49

S = 16.32 R-Sq = 60.80% R-Sq (adj) = 51.75% Pooled StDev = 16.32

ANOVA statistical analysis (95% confidence level): Amount of imiquimodthat is recovered following mass balance test from epidermis (fromresults that are presented in FIG. 60) is shown in Table 39:

TABLE 39 Source DF SS MS F P Cl 12 187.78 15.65 3.26 0.002 Error 52249.79 4.80 Total 64 437.57     Level     N     Mean     St. DevIndividual 95% CIs For Mean Based on Pooled StDev

3M Aldara ® 5% Imiquimod Cream 4 6.600 3.823

110 2.5% 6 3.248 1.717

250 2.5% 5 2.350 1.514

182 3.75% 6 3.643 2.083

195 3.75% 4 7.055 4.580

123 2.5% 5 4.196 3.782

125 2.5% 6 1.123 1.039

256 3.75% 5 1.990 1.588

197 3.75% 5 2.208 0.797

183 3.75% 4 3.260 1.053

126 5 2.360 0.903

Graceway Aldara ® 5% Imiquimod Cream 6 2.895 1.752

257 (1%) 4 0.415 0.273

S = 2.192 R-Sq = 42.91% R-Sq (adj) = 29.74% Pooled StDev = 2.192

ANOVA statistical analysis (95% confidence level): Amount of imiquimodthat is recovered following mass balance test from dermis (from resultsthat are presented in FIG. 60) is shown in Table 40:

TABLE 40 Source DF SS MS F P Cl 12 340.72 28.39 3.29 0.001 Error 52448.34  8.62 Total 64 789.06     Level     N     Mean     St. DevIndividual 95% CIs For Mean Based on Pooled StDev

3M Aldara ® 5% Imiquimod Cream 4 3.960 0.825

110 2.5% 6 2.323 1.068

250 2.5% 5 1.164 0.663

182 3.75% 6 6.937 5.445

195 3.75% 4 2.473 1.733

123 2.5% 5 1.796 0.715

125 2.5% 6 1.518 1.020

256 3.75% 5 9.030 5.305

197 3.75% 5 2.532 2.036

183 3.75% 4 5.110 4.638

126 5 4.436 3.626

Graceway Aldara ® 5% Imiquimod Cream 6 2.758 1.721

257 (1%) 4 1.533 2.099

S = 2.936 R-Sq = 43.18% R-Sq (adj) = 30.07% Pooled StDev = 2.936

The results that are presented in FIG. 61, indicate that the delivery ofthe imiquimod into the receiver fluid, epidermis and dermis combinedfrom formulations 182, 195 and 256 are similar to the Aldara® 5%imiquimod cream formulation when comparing averages. With respect to thestatistical analysis, there is no statistical difference (p>0.05)between 110 (2.5%), 126 (2.5%), 123 (2.5%), 182, (3.75%), 195 (3.75%),256 (3.75%), 197 (3.75%) and 183 (3.75%) when compared to Aldara® 5%imiquimod cream formulation in the amount of imiquimod that is recoveredfrom the receiver fluid, epidermis and dermis combined.

In Table 41, ANOVA statistical analysis (95% confidence level) arepresented: Total amount of imiquimod that is recovered for eachformulation in the receiver fluid, epidermis and dermis combined (fromthe results that are presented in FIG. 61:

TABLE 41 Source DF SS MS F P Cl 12 573.2 47.8 3.28 0.001 Error 52 758.214.6 Total 64 1331.4     Level     N     Mean     St. Dev Individual 95%CIs For Mean Based on Pooled StDev

257 (1%) 4  1.958 2.357

110 2.5% 6  5.572 2.706

250 2.5% 5  3.524 1.445

123 2.5% 5  6.010 4.296

125 2.5% 6  2.663 0.837

126 2.5% 5  6.804 3.538

182 3.75% 6 10.662 6.441

195 3.75% 4  9.608 5.392

256 3.75% 5 11.180 5.770

197 3.75% 5  4.800 1.749

183 3.75% 4  8.388 3.666

Graceway Aldara ® 5% Imiquimod Cream 6  5.682 2.671

3M Aldara ® 5% Imiquimod Cream 4 10.613 4.211

S = 3.819 R-Sq = 43.05% R-Sq (adj) = 29.91% Pooled StDev = 3.819

The results that are presented in FIG. 62 and statistical analysis inTables 42-46 indicate that there is a distinct dose proportionate trendbetween the amount of imiquimod that is recovered from each of thematrices with respect to the concentration of imiquimod in theformulation for both un-absorbed and Stratum corneum. The trend in thisdata, is also observed for the epidermis (with respect to average valuesin the statistical analysis).

In Tables 42-46, statistical analysis for the total amount of imiquimodrecovered from each of the matrices (1%, 2.5%, 3.75% and 5% w/wformulations)

ANOVA statistical analysis (95% confidence level): Total amount ofimiquimod that is recovered for imiquimod concentration combined fromeach of the matrices from un-absorbed dose (from results presented inFIG. 62) in Table 42:

TABLE 42 Source DF SS MS F P Cl 3 44198 14733 35.53 0.000 Error 61 25293415 Total 64 69491     Level     N     Mean     St. Dev Individual 95%CIs For Mean Based on Pooled StDev

1% 4 28.88 9.20

2.5% 27 64.08 16.24

3.75% 24 90.75 22.48

5% 10 129.33 26.99

S = 20.36 R-Sq = 63.60% R-Sq (adj) = 61.81% Pooled StDev = 20.36

ANOVA statistical analysis (95% confidence level): Total amount ofimiquimod that is recovered for imiquimod concentration combined fromeach of the matrices from Strateum corneum (from results presented inFIG. 62) in Table 43:

TABLE 43 Source DF SS MS F P Cl 3 19744 6581 25.76 0.000 Error 61 15583255 Total 64 35327     Level     N     Mean     St. Dev Individual 95%CIs For Mean Based on Pooled StDev

1% 4 12.49 7.49

2.5% 27 31.34 12.57

3.75% 24 43.74 15.85

5% 10 78.22 24.79

S = 15.98 R-Sq = 55.89% R-Sq (adj) = 53.72% Pooled StDev = 15.98

ANOVA statistical analysis (95% confidence level): Total amount ofimiquimod that is recovered for imiquimod concentration combined fromeach of the matrices from epidermis (from results presented in FIG. 62)in Table 44:

TABLE 44 Source DF SS MS F P Cl 3 55.25 18.42 2.94 0.040 Error 61 382.326.27 Total 64 437.57     Level     N     Mean     St. Dev Individual 95%CIs For Mean Based on Pooled StDev

1% 4 0.415 0.273

2.5% 27 2.621 2.137

3.75% 24 3.505 2.729

5% 10 4.377 3.200

S = 2.504 R-Sq = 12.63% R-Sq (adj) = 8.33% Pooled StDev = 2.504

ANOVA statistical analysis (95% confidence level): Total amount ofimiquimod that is recovered for imiquimod concentration combined fromeach of the matrices from dermis (from results presented in FIG. 62) inTable 45:

TABLE 45 Source DF SS MS F P Cl  3 147.4 49.1 4.67 0.005 Error 61 641.710.5 Total 64 789.1     Level     N     Mean   St. Dev Individual 95%CIs For Mean Based on Pooled StDev

1%  4 1.533 2.099

2.5% 27 2.223 1.974

3.75% 24 5.407 4.694

5% 10 3.239 1.502

S = 3.243 R-Sq = 18.68% R-Sq (adj) = 14.68% Pooled StDev = 3.243

ANOVA statistical analysis (95% confidence level): Total amount ofimiquimod that is recovered for imiquimod concentration combined fromeach of the matrices from receiver fluid (from results presented in FIG.62) in Table 46:

TABLE 46 Source DF SS MS F P Cl 3 0.07047 0.02349 4.28 0.008 Error 610.33483 0.00549 Total 64 0.40530     Level     N     Mean     St. DevIndividual 95% CIs For Mean Based on Pooled StDev

1%  4 0.00500 0.00577

2.5% 27 0.00926 0.01542

3.75% 24 0.08083 0.11632

5% 10 0.03800 0.04392

S = 0.07409 R-Sq = 17.39% R-Sq (adj) = 13.32% Pooled StDev = 0.07409

The following Tables 47-59 summarize results for formulations 126, 182and Pbo4.

TABLE 47 Stability of Imiquimod in the Formulations. Percentage ofimiquimod that is recovered from each formulation compared totheoretical when stored at 25° C. and 40° C. over a 6 month period. For-t = 1 month t = 2 months t = 3 months t = 6 months mulations t = 0 h 25°C. 40° C. 25° C. 40° C. 25° C. 40° C. 25° C. 40° C. 182 96.76 ± 0.25102.01 ± 0.01 98.46 ± 0.15 99.00 ± 0.12 98.07 ± 0.10 101.48 ± 0.27104.39 ± 1.55 102.91 ± 1.16 99.12 ± 0.45 PBO4 0 0 0 0 0 0 0 0 0 126102.37 ± 102.84 ± 0.45 104.11 ± 100.02 ± 101.32 ±  99.28 ± 3.25  98.43 ±0.55 101.95 ± 0.37 103.02 ± 0.58 0.04 0.95 040 1.89

TABLE 48 Stability of Imiquimod in the Formulations. Identification ofImiquimod when the formulations are stored at 25° C. and 40° C. over a 6month period (confirmed by HPLC). T = 1 month T = 2 months T = 3 monthsT = 6 months Formulations T = 0 25° C. 40° C. 25° C. 25° C. 40° C. 40°C. 25° C. 40° C. 182 Complies Complies Complies Complies CompilesComplies Complies Compiles Complies 126 Complies Complies CompliesComplies Complies Complies Complies Complies Complies GWO3OP CompliesComplies Complies Complies Complies Complies Complies Complies Complies

TABLE 49 Stability of Benzyl Alcohol in the Formulations. Amount ofbenzyl alcohol that is recovered from each of the formulations when theformulations are stored at 25° C. and 40° C. over a 6 month period.Formu- t = 1 month t = 2 months t = 3 months t = 6 months lations t = 0h 25° C. 40° C. 25° C. 40° C. 25° C. 40° C. 25° C. 40° C. 182 2.17 ±0.00 2.17 ± 0.00 1.95 ± 0.01 2.11 ± 0.04 1.97 ± 0.00 1.94 ± 0.01 1.82 ±0.04 1.85 ± 0.03 1.48 ± 0.05 PBO4 1.93 ± 0.02 1.83 ± 0.06 1.90 ± 0.031.91 ± 0.01 1.53 ± 0.00 1.81 ± 0.01 1.39 ± 0.01 1.71 ± 0.01 1.08 ± 0.02126 2.00 ± 0.02 2.02 ± 0.01 1.89 ± 0.01 1.86 ± 0.02 1.65 ± 0.02 2.00 ±0.04 1.70 ± 0.04 2.01 ± 0.03 1.55 ± 0.02

TABLE 50 Stability of Benzyl Alcohol in the Formulations. Identificationof Benzyl alcohol when the formulations are stored at 25° C. and 40° C.over a 6 month period (confirmed by HPLC). T = 1 month T = 2 months T =3 months T = 6 months Formulations T = 0 25° C. 40° C. 25° C. 25° C. 40°C. 40° C. 25° C. 40° C. 182 Complies Complies Complies Complies CompilesComplies Complies Compiles Complies 126 Complies Complies CompliesComplies Complies Complies Complies Complies Complies PBO4 CompliesComplies Complies Complies Complies Complies Complies Complies Complies

TABLE 51 Stability of Methylparabens in the Formulations. Amount ofMethylparabens that are recovered from each of the formulations when theformulations are stored at 25° C. and 40° C. over a 6 month period.Formu- t = 1 month t = 2 months t = 3 months t = 6 months lations t = 0h 25° C. 40° C. 25° C. 40° C. 25° C. 40° C. 25° C. 40° C. 182 0.18 ±0.001 0.18 ± 0.000 0.19 ± 0.001 0.20 ± 0.001 0.20 ± 0.000 0.19 ± 0.0000.20 ± 0.004 0.19 ± 0.002 0.19 ± 0.001 PBO4 0.19 ± 0.00 0.19 ± 0.0030.18 ± 0.002 0.20 ± 0.001 0.20 ± 0.000 0.20 ± 0.001 0.20 ± 0.001 0.20 ±0.001 0.20 ± 0.002 126 0.20 ± 0.002 0.20 ± 0.001 0.19 ± 0.000 0.19 ±0.001 0.21 ± 0.00  0.21 ± 0.001 0.20 ± 0.001 0.20 ± 0.001 0.20 ± 0.001

TABLE 52 Stability of Methylparabens in the Formulations. T = 1 month T= 2 months T = 3 months T = 6 months Formulations T = 0 25° C. 40° C.25° C. 25° C. 40° C. 40° C. 25° C. 40° C. 182 Complies Complies CompliesComplies Compiles Complies Complies Compiles Complies 126 CompliesComplies Complies Complies Complies Complies Complies Complies CompliesPBO4 Complies Complies Complies Complies Complies Complies CompliesComplies Complies Identification of Methylparabens when the formulationsare stored at 25° C. and 40° C. over a 6 month period (confirmed byHPLC).

TABLE 53 Stability of Propylparabens in the Formulations. t = 1 month t= 2 months Formulations t = 0 h 25° C. 40° C. 25° C. 40° C. 182 0.019 ±0.000 0.020 ± 0.001 0.018 ± 0.000 0.018 ± 0.000 0.018 ± 0.000 PBO4 0.018± 0.001 0.018 ± 0.001  0.16 ± 0.001  0.19 ± 0.000 0.020 ± 0.000 1260.018 ± 0.000 0.019 ± 0.001 0.021 ± 0.001 0.018 ± 0.000 0.019 ± 0.001 t= 3 months t = 6 months Formulations 25° C. 40° C. 25° C. 40° C. 1820.021 ± 0.002 0.022 ± 0.001 0.019 ± 0.000  0.019 ± 0.0010 PBO4 0.020 ±0.002 0.020 ± 0.002 0.018 ± 0.000 0.020 ± 0.001 126 0.020 ± 0.001 0.010± 0.001 0.020 ± 0.000 0.020 ± 0.001 Amount of Propylparabens that arerecovered from each of the formulations when the formulations are storedat 25° C. and 40° C. over a 6 month period.

TABLE 54 Stability of Propylparabens in the Formulations. T = 1 month T= 2 months T = 3 months T = 6 months Formulations T = 0 25° C. 40° C.25° C. 25° C. 40° C. 40° C. 25° C. 40° C. 182 Complies Complies CompliesComplies Compiles Complies Complies Compiles Complies 126 CompliesComplies Complies Complies Complies Complies Complies Complies CompliesPBO4 Complies Complies Complies Complies Complies Complies CompliesComplies Complies Identification of Propylparabens when the formulationsare stored at 25° C. and 40° C. over a 6 month period (confirmed byHPLC).

TABLE 55 Microscopic Stability of the Formulations. The results of theparticle size for each formulation which is determined by opticalmicroscopy at 25° C. over a 6 month period. Particle size (μM) t = 2Formulation t = 0 t = 1 Month Months t = 3 Months t = 6 Months 182 <10<10 <10 <10 <10 PBO4 <10 <10 <10 <10 <10 126 <10 <10 <10 <10 <10

TABLE 56 pH stability of the Formulations. pH t = 0 t = 1 month t = 2months t = 3 months t = 6 months Formulation 25° C. 25° C. 40° C. 25° C.40° C. 25° C. 40° C. 25° C. 40° C. 182 4.5 4.5 4.5 4.5 4.5 4.6 4.3 4.3PBO4 4.5 4.2 4.5 4.2 4.2 4.1 4.1 4.0 4.0 126 4.2 4.3 4.3 4.3 4.3 4.3 4.34.1 4.1 The results of the pH test for each of the formulations when theformulations are stored at 25° C. and 40° C. over a 6 month period. Greyarea indicate no test was performed.

TABLE 57 Macroscopic stability of the Formulations. Appearance spatulaTest (25° C. sample only) Visual Viscosity (25° C. sample only) t = 1 t= 2 t = 3 t = 6 t = 1 t = 2 t = 3 t = 6 Formulation t = 0 month monthsmonths months t = 0 month months months months 182 Very glossy Veryglossy Very Very glossy Very glossy High Medium- Medium- Medium- Highand smooth and smooth glossy and and smooth and smooth High High Highsmooth 126 Glossy, very Smooth, Glassy and Slightly Glossy Medium MediumMedium Medium Low slightly slightly smooth textured, viscosity texturedtextured, sheen glossy PBO4 Glossy and Glossy and Glossy and Glossy andSmooth Medium- Medium Medium- Low Low smooth smooth smooth smooth creamhigh Low Low sheen The results of the macroscopic appearance test whenthe formulations are stored at 25° C. over a 6 month period.

TABLE 58 Brookfield and Bohlin Viscosity. Cross- over Brookfield (cPs)Bohlin Viscosity (cPs) (based on 3M method) Formulation G*(Pa) (o*) t =1 t = 2 t = 3 t = 6 t = 1 t = 2 t = 3 t = 6 Identity t = 0 t = 0 t = 0Month Months Months Months t = 0 Month Months Months Months 182 702 8.5693067 1097000 904667 523033 273233 18050 17850 18550 16820 13691 126 **** 430100 235066 228104 212500 105720 16783 12739 14749 10856.5 8789.5PBO4 ** ** 227800 * * * * 10350 7953 5511 3550 2247 The results of theviscosity and rheology measurements for the formulations that are storedat 25° C. over a 6 month period. * Results not presented as the torqueis out of range (due to low viscosity) for the Brookfields viscometerbased on the setting and spindle that are used for all the othersamples. Alternative spindles and settings are investigated; however,the results are vastly different compared to previous readings. ** norecorded measurements.

TABLE 59 Identification of 4-hydroxy Imiquimod when the formulations arestored at 25° C. and 40° C. over a 6 month period (confirmed by HPLC at318 nm). t = 1 t = 2 t = 3 t = 6 t = 0 month months months monthsFormulations 25° C. 25° C. 40° C. 25° C. 40° C. 25° C. 40° C. 25° C. 40°C. 182 NMT NMT NMT NMT NMT NMT NMT NMT NMT 0.1% 0.1% 0.1% 0.1% 0.1% 0.1%0.1% 0.1% 0.1% w/w w/w w/w w/w w/w w/w w/w w/w w/w PBO4 NMT NMT NMT NMTNMT NMT NMT NMT NMT 0.1% 0.1% 0.1% 0.1% 0.1% 0.1% 0.1% 0.1% 0.1% w/w w/ww/w w/w w/w w/w w/w w/w w/w 126 NMT NMT NMT NMT NMT NMT NMT NMT NMT 0.1%0.1% 0.1% 0.1% 0.1% 0.1% 0.1% 0.1% 0.1% w/w w/w w/w w/w w/w w/w w/w w/ww/w

Example 24 Four Phase 3 Randomized, Double-Blinded, Multicenter,Placebo-Controlled Clinical Studies

In this Example 24, four Phase 3 randomized, double-blinded,multicenter, placebo-controlled clinical studies comparing the efficacyand safety of a 3.75% imiquimod cream of Example 23 and a 2.5% imiquimodcream of Example 23 to placebo in the treatment of typical visible orpalpable actinic keratoses of the face or balding scalp. Subjects, whoare determined to be eligible during the screening phase, are randomizedin a 1:1:1 ratio to receive either 2.5% imiquimod cream, 3.75% imiquimodcream or placebo cream once daily during the treatment cycles. StudiesGW01-0702 and GW01-0704 are duplicative studies that investigate 2-weektreatment cycles, wherein the 2-week treatment cycles are separated by atwo week rest period (no treatment), and studies GW01-0703 and GW01-0705are duplicative studies that investigate 3-week treatment cycles,wherein the 3-week treatment cycles are separated by a three week restperiod (no treatment). See flow diagrams depicted in FIG. 70 and seeTable 64 herein below. The study entry criteria and endpoints areidentical for all four studies. Each study has the same length of a posttreatment follow-up period in which the primary endpoint in all fourstudies is at 8 weeks following the last treatment application. Thus,four Phase 3 clinical studies with two formulations (2.5% and 3.75%imiquimod creams) and one pharmacokinetic study (Example 25) with oneformulation of 3.75% imiquimod cream are conducted for the treatment ofactinic keratosis diagnosed on the face or balding scalp. See also theFINAL LABEL and the PRODUCT MONOGRAPH, which are filed contemporaneouslyherewith and incorporated herein by reference in their entireties. Alsoincorporated herein by reference in their entireties are the followingstudies identified as follows: (1) Sponsored and information providedby: Graceway Pharmaceuticals, LLC, Study entitled “Safety andEffectiveness Study of Imiquimod Creams for Treatment of ActinicKeratoses [Aks]”, and ClinicalTrials.gov Identifier No.: NCT00605176;(2) Sponsored and information provided by: Graceway Pharmaceuticals,LLC, Study entitled “Safety and Effectiveness Study of Imiquimod Creamsfor Treatment of Actinic Keratoses [Aks]”, and ClinicalTrials.govIdentifier No.: NCT00603798; and (3) Sponsored and information providedby: Graceway Pharmaceuticals, LLC, Study entitled “Follow-up Study toEvaluate Sustained Clearance Rates of Actinic Keratoses up to One Year”,and ClinicalTrials.gov Identifier No.: NCT00668733. The four Phase 3clinical studies with two formulations (2.5% and 3.75% imiquimod creams)and the one pharmacokinetic study (Example 25) are summarized asfollows:

In Example 25, a pharmacokinetic study conducted under maximal useconditions (Study GW01-0706) is described as indicated above.

Four randomized, double-blinded, placebo-controlled Phase 3 clinicalstudies (differing only in the duration of treatment and intervalcycles) are characterized as follows:

1. Studies GW01-0702 & GW01-0704 (2-week treatment cycle regimen): twoidentical studies evaluating 2.5% imiquimod cream, 3.75% imiquimod creamor placebo cream which is applied daily for two 2-week treatment cycles.The first treatment cycle consists of two weeks of daily treatmentfollowed by two weeks of no treatment, and the second treatment cycleconsists of an additional two weeks of daily treatment followed by eightweeks of post treatment follow-up period (total study duration 14weeks); and

2. Studies GW01-0703 & GW01-0705 (3-week treatment cycle regimen): twoidentical studies evaluating 2.5% imiquimod cream, 3.75% imiquimod creamor placebo cream which is applied daily for two 3-week treatment cycles.The first treatment cycle consists of three weeks of daily treatmentfollowed by three weeks of no-treatment, and the second treatment cycleconsists of an additional three weeks of daily treatment followed byeight weeks of post treatment follow-up period (total study duration 17weeks).

The clinical studies are displayed in Table 61 below. All 4 Phase 3studies are conducted at separate study sites to provide independentconfirmatory evidence of safety and efficacy. The results from thesestudies are evaluated and based on the safety and efficacy results fromall four studies.

TABLE 61 Summary of Studies of Imiquimod for the Actinic Keratosis StudyNum- Num- ber of ber/ Sub- Status jects Treatments Brief StudyDescription/Comments GW01- 19 Two 250 mg Pharmacokinetic study is 0706packets of 3.75% conducted under maximal use imiquimod is conditions inAK subjects. Study applied to the entire designed to demonstrate steady-face or balding scalp state conditions. every day for 3 weeks GW01- 242Up to two 250 mg Phase 3 study of the 2-week 0702 packets are appliedtreatment cycle regimen (2 weeks to the entire face or on treatment, 2weeks of no balding scalp treatment, followed by 2 weeks on 2.5%imiquimod treatment). cream every day for Primary endpoint of completetwo 2-week clearance at 8 weeks after treatment cycles treatment (Week14; End Of 3.75% imiquimod Study—EOS) cream every day for two 2-weektreatment cycles Placebo every day for two 2-week treatment cycles GW01-237 Same treatments as Duplicate of study 02 is conducted 0704 Study 02at independent study centers. GW01- 240 Up to two 250 mg Phase 3 studyof the 3-week 0703 packets are applied treatment cycle regimen (3 weeksto the entire face or on treatment, 3 weeks of no balding scalptreatment, followed by 3 weeks on 2.5% imiquimod treatment). every dayfor two 3- Primary endpoint of complete week treatment clearance at 8weeks after cycles treatment (Week 17; EOS) 3.75% imiquimod every dayfor two 3- week treatment cycles Placebo every day for two 3-weektreatment cycles GW01- 250 Same treatments as Duplicate of Phase 3 study03 is 0705 Study 03 conducted at independent study centers.

All four Phase 3 studies are randomized, double-blinded, multicenter,placebo-controlled studies comparing the efficacy and safety of 3.75%imiquimod cream and 2.5% imiquimod cream to placebo in the treatment oftypical visible or palpable actinic keratoses of the face or baldingscalp. Subjects determined to be eligible during the screening phase arerandomized in a 1:1:1 ratio to receive either 3.75% imiquimod cream,2.5% imiquimod cream or placebo cream once daily during the treatmentcycles. Studies GW01-0702 and GW01-0704 investigate two 2-week treatmentcycles that are separated by a two weeks of no treatment, and studiesGW01-0703 and GW01-0705 investigate two 3-week treatment cycles that areseparated by three weeks of no treatment.

Studies GW01-0702 and GW01-0704 are conducted concurrently according toidentical protocols. A total of approximately 479 subjects arerandomized in a 1:1:1 ratio (approximately 240 to each treatment arm) toachieve approximately 450 subjects completing the study. The treatmentarms are:

2.5% imiquimod cream

3.75% imiquimod cream

placebo cream

Eligible subjects for the study are at least 18 years of age, with about5 to 20 typical visible or palpable actinic keratosis lesions (AKs) inan area that exceeded 25 cm² on either the face or the balding scalp.The treatment area could be either the entire face, excluding the ears,or the balding scalp, but not both. Apart from the primary diagnosis,the subjects are to be in good general health, and free of conditionswhich might put them at undue risk during study procedures. They mustnot use imiquimod cream on the face or scalp within 1 year of studyentrance, nor use other potentially interfering medications withinpre-specified washout intervals prior to study entrance.

The randomized, blinded study product is used in 2 treatment cycles eachof 2 weeks duration, separated by a 2-week period without treatment.Once a day during the treatment cycles, subjects apply the study creamin a thin layer to the entire treatment area. A maximum of 2 packets(i.e., up to 500 mg) could be applied for a given dose. The study creamis applied prior to normal sleeping hours and is removed approximately 8hours later with mild soap and water.

During the 2 treatment cycles of 2 weeks, subjects are scheduled for atotal of 9 study visits:

Visit 1, Screening

Visit 2, Baseline, Cycle 1 Treatment Initiation

Visit 3, Week 1

Visit 4, Week 2, End of Cycle 1

Visit 5, Week 4, Cycle 2 Treatment Initiation

Visit 6, Week 5

Visit 7, Week 6, End of Cycle 2 (End of Treatment)

Visit 8, Week 10, Follow-up

Visit 9, Week 14, End of Study, Primary Efficacy Endpoint

The objective of the studies is to compare the safety and efficacy of2.5% imiquimod cream and 3.75% imiquimod cream vs. placebo in thetreatment of actinic keratosis when the cream is applied once daily fortwo 2-week treatment cycles separated by a 2-week no-treatment period.

The two additional Phase 3 studies, GW01-0703 and GW01-0705, areconducted concurrently according to identical protocols. These studiesare also randomized, double-blind, multicenter, placebo-controlledtrials identical to the pivotal studies in all respects except for theduration of the treatment regimens and corresponding differences invisit schedules. The planned number of subjects, randomizationmethodology, entrance criteria, and study drug formulations are the sameas in the two Phase 3 GW01-0702 and GW01-0704 studies trials.

As in the GW01-0702 and GW01-0704 studies, the randomized, blinded studyproducts are used in two 2-week treatment cycles, but in GW01-0703 andGW01-0705, the treatment cycles are of three weeks duration, separatedby a 3-week period without treatment.

During the two treatment cycles of three weeks, subjects are scheduledfor a total of 11 study visits:

Visit 1, Screening

Visit 2, Baseline, Cycle 1 Treatment Initiation

Visit 3, Week 1

Visit 4, Week 2

Visit 5, Week 3, End of Cycle 1

Visit 6, Week 6, Cycle 2 Treatment Initiation

Visit 7, Week 7

Visit 8, Week 8

Visit 9, Week 9, End of Cycle 2 (End of Treatment)

Visit 10, Week 13, Follow-up

Visit 11, Week 17, End of Study, Primary Efficacy Endpoint

Thus, two pairs of 2 identical Phase 3 studies (four Studies) regardingefficacy and safety of four and six weeks of treatment with imiquimodformulations for actinic keratosis are conducted. See Table 62. Eachpair evaluates a different treatment regimen and each individual studycontains two imiquimod concentrations, i.e., 2.5% and 3.75% imiquimodformulations with comparisons to placebo (double-blinded).

TABLE 62 Four Clinical Trials 2 × 2 × 2 wks GW01-0702  2.5% (N = 81) L23.75% (N = 81) H2 Vehicle (N = 80) V 2 × 2 × 2 wks GW01-0704  2.5% (N =79) L2 3.75% (N = 79) H2 Vehicle (N = 79) V 3 × 3 × 3 wks GW01-0703 2.5% (N = 82) L3 3.75% (N = 80) H3 Vehicle (N = 78) V 3 × 3 × 3 wksGW01-0705  2.5% (N = 82) L3 3.75% (N = 82) H3 Vehicle (N = 82) V

The study design is as summarized in Table 63—Study Designs below.

TABLE 63 Study Designs 2 Cycles + 8 wks Follow-up Cycle 1 Cycle 2 No TXNo TX Daily TX Rest Period Daily TX Follow up 2 or 3 wks 2 or 3 wks 3 ×3 × 3 study 8 wks - Endpoint is determined at end of week 14 for the 2 ×2 × 2 study or week 17 for the

In contrast, the FDA approved treatment regimen for treating actinickeratosis with Aldara® 5% imiquimod cream is two times per week for 16weeks and end point is determined at end of week 24.

The key entry criteria for these four studies are: (1) 18 years of ageor greater; (2) 5-20 AKs in treatment area; (3) the treatment areaexceeds 25 cm²; and (4) the treatment area is either full face orbalding scalp, but not both. As a historical reference, the FDA approvedtreatment area for Aldara® 5% imiquimod cream is 25 cm² and the numberof AK lesions treated in the treatment area is generally between 4 and8.

Key efficacy measures for these four studies are a reduction of AKlesions from Baseline to End of Study (Week 14 or 17):

-   -   Primary: complete clearance (yes/no)*    -   Secondary: at least 75% reduction in number of AK lesions        (partial clearance yes/no)*    -   Secondary: percent reduction in number of AK lesions analyzed as        a continuous variable    -   All AK lesions that are cleared including newly arising        sub-clinical lesions

The protocol for the two pairs of identical phase three studies (4Studies) includes: (1) voluntary rest periods of any length duringtreatment cycles are permitted; (2) the subjects keep to original studyschedule irrespective of rest periods or missed doses; and (3) thesubjects apply the imiquimod formulation in Cycle 2 irrespective ofclearance in Cycle 1.

The key safety measures for the study are: (1) adverse events; (2) localskin reactions (LSRs), including (a) area under the curve (AUCsum) and(b) erythema (includes severe); (3) rest periods; and (4) studydiscontinuations.

The study treatment regimens are described in Table 64 and depicted inthe flow diagram(s) illustrated in FIG. 70.

TABLE 64 Study Treatment Regimen Study Treatment Regimen GW01-0702  2.5%Daily, 2 × 2 × 2 weeks, see FIG. 70 GW01-0704 3.75% Daily, 2 × 2 × 2weeks, see FIG. 70 GW01-0703  2.5% Daily, 3 × 3 × 3 weeks, see FIG. 70GW01-0704 3.75% Daily, 3 × 3 × 3 weeks, see FIG. 70

The LSR AUC sum is defined as follows:

(1) LSRs (0-3 scale)

-   -   Erythema    -   Edema    -   Weeping/exudate    -   Scabbing/crusting    -   Flaking/scaling/dryness    -   Erosion/ulceration*

0-2 scale

(2) AUC_(sum)

-   -   Sum of individual LSR Scores    -   Over study duration (14 or 17 weeks; includes 4 or 6 weeks on        treatment)

The population of the study is summarized in the Table 65—Populationbelow and as follows:

-   -   (1) 969 AK subjects enrolled to 4 studies;    -   (2) 646 subjects are randomized to active imiquimod cream:        -   160 to 2.5% imiquimod cream, 2-week cycles        -   160 to 3.75% imiquimod cream, 2-week cycles        -   164 to 2.5% imiquimod cream, 3-week cycles        -   162 to 3.75% imiquimod cream, 3-week cycles; and    -   (3) The subjects are enrolled at 51 sites geographically        distributed in the USA, wherein:        -   Median number of subjects enrolled per site: 18        -   Range: 2 to 34.

TABLE 65 Population H2 L2 3.75% L3 H V 2.5% 2 W 2 W 2.5% 3 W 3.75% 3 WVehicle (N = 160) (N = 160) (N = 164) (N = 162) (N = 323) Age, 64(39-90) 64 (36-89) 66 (33-87) 64 (40-90) 64 (37-89) Mean (Range) Sex, 7983 78 76 82 % male Race 100  100  100  99 99 % white Treatment 73/2776/2 70/30 71/2 75/25 Area, % Face/ Scalp Skin 84 87 88 90 86 Type, % I,II, and III Baseline 10.9/10.0 11.0110.0 10.6/10.0 11.1/9.0 10.8/10.0Count, Mean/ Median

A summary of drug exposure and compliance is set forth in the Table 66Drug Exposure/Compliance below.

TABLE 66 Drug Exposure/Compliance L2 H2 L3 H 2.5% 3.75% 2.5% 3.75% V 2Week 2 Week 3 Week 3 Week Vehicle (N = 160) (N = 160) (N = 164) (N =162) (N = 323) Average 1.71 1.62 1.68 1.67 1.70 Number of Packets UsedPer Application Number (%) 2 (1.3) 9 (5.6) 69 (3.7) 9 (5.6) 14 (4.4)Subjects Non- compliant*

The following efficacy and safety results are observed and reported inFIGS. 1-24 and 51-52:

(1) all active treatment groups show statistically significantdifferences from vehicle in all efficacy measures; and

(2) there are no consistent statistically significant differencesbetween the 2.5% and 3.75% treatment groups (*) within each of thestudies;

-   -   Partial clearance is significantly different between L2 and H2        in the GW01-0704 study, but not in the GW01-0702 study;    -   Percent reduction between L2 and H2 in PP GW01-0704 study and PP        GW01-0702 study, not in ITT population.    -   Percent reduction between L3 and H3 in PP GW01-0705 study, not        in ITT population and not in GW01-07023 study.

Primary analysis populations are defined prospectively for the analysis.The primary population to be analyzed for efficacy and safety is theIntent-To-Treat (“ITT”) population, including all randomized subjects.The Per Protocol (“PP”) population includes subjects who complete thestudy without any protocol violations. Subjects are excluded from the PPpopulation if any of the following criteria are met.

-   -   Failure to meet Inclusion/Exclusion criteria    -   Took restricted medications/treatments    -   Nonadherence to the visit schedule    -   Noncompliance with study treatment

The investigators determine the treatment area for the studies atbaseline (either the entire face or the balding scalp, but not both).Subjects are instructed to apply a thin layer of study medication to thetreatment area, up to two packets (up to 500 mg) of product, avoidingthe periocular areas, lips and nares. Subjects return for clinic visitsover the course of the study for efficacy and safety measurements.

Actinic keratosis lesions arise on a background of UV-damaged skin, andtherefore, usually occur over an extensive area or field of sun-exposedskin. The creams are applied to the entire face or balding scalp, andnot just the 5-20 individual lesions required for study entry.Application to the full face of balding scalp provides clear directionto subjects regarding the area to be treated without reference to theexact location of lesions; additionally application to the full face orbalding scalp has the potential to treat sub-clinical or incipientlesions. Two concentrations of imiquimod cream (2.5% and 3.75%) are usedand compared to placebo for each study regimen, allowing a directcomparison of the concentrations for study outcomes.

As indicated above, treatment cycles of two or three weeks are chosenfor these Phase three studies. It is observed that sizable numbers ofsubjects receiving the 5% imiquimod cream two or three times a week takerest periods typically at the 4-6 week point in therapy. The need forrest periods is usually preceded by an increase at ˜2-3 weeks in signsand symptoms of local skin reactions. Cycle treatment (two cycles ofthree times a week for four consecutive weeks) appears to reduce but noteradicate the need for rest periods among subjects. The current Phasethree studies investigate daily dosing (for two or three weeks) followedby an interval of two or three weeks of no treatment before repeatinganother two- or three-week treatment cycle. This ‘no treatment period’is expected to occur after the initial onset of signs and symptoms whichherald the onset of pharmacodynamic effects of imiquimod treatment.

Subjects were instructed to apply the cream for a second treatment cycleirrespective of the degree of lesion clearance with the initialtreatment cycle. This is consistent with the current Aldara® packageinsert, which mandates a full 16 weeks of treatment irrespective ofinterim treatment response. The use of two treatment cycles allows for auniform assessment point for all subjects at 8 weeks following thetermination of the second treatment cycle, irrespective of initialtreatment response. The two-cycle treatment course is anticipated tohave a beneficial effect on ‘sub-clinical’ lesions. Previous studiessuggest that these lesions may become visible approximately two weeksinto a treatment course. A second treatment cycle has the potential totreat both residual clinically evident AK lesions as well as anysub-clinical lesions.

AK lesions are counted at study visits to derive the one primary(Complete Clearance) and two secondary (Partial Clearance, Percent AKreduction) efficacy endpoints. To meet the Complete Clearance primaryefficacy endpoint, subjects needed to be clear of all lesions in thetreatment area, irrespective of whether those lesions were identified atbaseline or later.

The primary efficacy variable is subject status with respect to completeclearance of AK lesions at the end of study (EOS; 8 weeks following thelast scheduled dose). The EOS visits occurred at Week 14 for theGW01-0702/GW01-0704 studies, and at Week 17 for the GW01-0703/GW01-0705studies. Complete clearance was defined as the absence of clinicallyvisible or palpable AK lesions in the treatment area.

The secondary efficacy variables are:

-   -   Subject status with respect to partial clearance of AK lesions        at EOS, defined as at least about a 75% reduction in the number        of AK lesions in the treatment area compared with Baseline;    -   Percent change (reductions) from Baseline to EOS in investigator        counts of AK lesions.

The statistical methods for efficacy analyses are the same in all fourPhase 3 studies.

Efficacy analyses are conducted on the ITT population and on the PPpopulation. For the primary efficacy variable, imputations are made formissing data points using last observation carried forward (LOCF,primary analysis), taking all missed observations as failure(sensitivity analysis), and using observed cases only (supportiveanalysis). The PP population analysis uses only cases that are observed.For analysis of secondary efficacy variables, only the LOCF method isused for the ITT population, and only cases that are observed for the PPpopulation. All data from interim visits (before EOS/Early Termination)are analyzed at their nominal time points.

The allowed visit window at EOS, is any time more than 42 days after thedate of last dose (or last rest). Subjects with no EOS visit areexcluded from the PP population. In the ITT population, subjects withoutan in-window EOS visit are analyzed using the LOCF.

All pairwise comparisons of active treatment versus placebo are madeusing Hochberg's modified Bonferroni procedure. If either test issignificant at a 0.025 level of significance, then that test isconsidered significant. Otherwise, if both tests are significant at0.05, then both tests are considered significant. The 3.75% and 2.5%imiquimod treatment groups are compared to each other at the 0.05 levelof significance if at least one of these treatment groups is found to bedifferent than the placebo using the Hochberg's test.

In this way, complete clearance rates, partial clearance rates, changefrom Baseline AK lesion counts, and percent change from baseline AKlesion counts are analyzed using Cochran-Mantel-Haenszel (CMH)statistics, stratifying on center.

If at least one of the active arms is found to be superior to placebo inthe primary efficacy variable of complete clearance, the secondaryefficacy variable of partial clearance is compared between each of theactive arms and placebo using Hochberg's modified Bonferroni procedure.If the secondary efficacy variable of partial clearance is found to besuperior to placebo in either of the active treatment groups, then thesecondary efficacy variable of percent reduction is tested. Tertiaryefficacy variables are tested without adjustment for multiplicity at thenominal 5% level.

In order to obtain at least 6 subjects per center per treatment group,investigational centers yielding fewer than 18 subjects are combinedtogether in order of geographical proximity. The exact composition ofthese “analysis centers” is determined and documented prior to breakingthe study blind. The stratification for CMH analyses is based on theanalysis centers, not on the actual investigational centers.

In the primary analysis of complete clearance rate, the Breslow-Daystatistic is tested at the 10% level for heterogeneity of the oddsratios across analysis centers. A finding of statistical significance inthis test is followed by exploratory analyses to characterize the sourceof the heterogeneity.

The primary efficacy variable is summarized without statistical testingby success frequency by investigator center, by analysis center, bygender, by age subgroup, by skin type subgroup, by baseline lesion countsubgroup, and by treatment area (face or balding scalp).

Subjects who show a greater number of AK lesions at any timepost-baseline compared to the baseline lesion count are of particularinterest since the new lesions may represent sub-clinical lesions whichare present but unobserved at the baseline visit. The proportion ofsubjects who show new lesions while on treatment are presented bytreatment group, and the primary efficacy variable is summarized in thissubject subgroup.

All safety measures are analyzed using the ITT data set. Safety isassessed by collection of adverse events which are fully characterizedas to intensity, seriousness and relationship to study drug.Additionally, local skin reactions (LSRs) are anticipated adverse eventsrelated to the pharmacodynamic activity of the drug; therefore, LSRs areassessed by the investigator at each study visit. Six LSRs (erythema,edema, weeping/exudate, flaking/scaling/dryness, scabbing/crusting, anderosion/ulceration) are rated by the investigator at each study visit ona 0-3 scale (save erosion/ulceration rated 0-2). Data relating to restperiods are collected. Vital signs and laboratory data are collectedprestudy or baseline and at end of study.

Adverse events (AEs) are coded using Medical Dictionary for RegulatoryActivities (MedDRA) terminology. Treatment-emergent AEs are summarizedfor each treatment group by the overall incidence of at least one event,incidence by system organ class, and incidence by system organ class andpreferred term. Treatment-emergent AEs are also summarized by severity,and by relationship to study product. The AE incidence is summarized bygender, by age subgroup, by skin type subgroup, by baseline lesion countsubgroup, and by location of treatment area (face or balding scalp).Serious AEs and discontinuations due to AEs are listed by subject.

The intensity of each local skin reaction (LSR) type (erythema, edema,weeping/exudate, flaking/scaling/dryness, scabbing/crusting, anderosion/ulceration) and the most intense reaction (post-baseline) foreach type are summarized by frequency counts and mean scores bytreatment group and study visit. An LSR sum score is computed at eachstudy visit, and 3 areas under the curve (AUC, in days) are calculated;from Baseline to beginning of Treatment Cycle 2, from beginning ofTreatment Cycle 2 to End of Study (EOS), and from Baseline to EOS. Thesevalues are compared pairwise between treatment groups using Fisher'sleast significant differences in the 1-way analysis of variance(treatment group).

The number and percentage by treatment group of subjects who require arest period (1 or more, by treatment cycle and overall) are analyzedusing CMH statistics. A similar analysis summarized the number andpercentage of subjects by treatment group (1) who require a rest periodin both treatment cycles, (2) who require a rest period in Cycle 1 only,and (3) who require a rest period in Cycle 2 only. The number of dosingdays missed due to rest periods and the number of dosing days prior tothe beginning of the first rest period are analyzed using nonparametricCMH methods for each treatment cycle and overall.

Clinical laboratory values are listed, and frequency counts in alertstatus shifts are tabulated.

The preliminary results from each of the Phase 3 clinical studies aresummarized in the sections below, with the results of paired identicalstudies (GW01-0702/GW01-0704 and GW01-0703/GW01-0705 presented side byside). Overall, a total of 969 subjects are enrolled into the four Phase3 studies. Fifty-one independent sites in the United States enrolledsubjects in the Phase 3 studies. The number of subjects that areincluded in the ITT Data sets are tabulated in Table 67.

TABLE 67 Number of Subjects Included in the ITT Data Sets Study 3.75%IMIQ 2.5% IMIQ Placebo Overall GW01-0702 81 81 80 242 GW01-0704 79 79 79237 Combined 2-Week 160 160 159 479 Treatment Cycle Regimen StudiesGW01-0703 80 82 78 240 GW01-0705 82 82 86 250 Combined 3-Week 162 164164 490 Treatment Cycle Regimen Studies

Studies of Two-Week Treatment Cycles

Preliminary data from the Two-week Treatment Cycle Studies (GW01-0702and GW01-0704) are presented below.

Subject Disposition for studies GW01-0702 and GW01-0704 is tabulated inTable 68.

TABLE 68 Subject Disposition; Two-Week Treatment Cycle Regimen StudiesGW01-0702 GW01-0704 2.5% 3.75% 2.5% 3.75% IMIQ IMIQ Placebo IMIQ IMIQPlacebo Total no. of subjects, n (%) Randomized 81  81  80  79  79  79 Completed Study ^(a) 78 (96.3) 74 (91.4) 75 (93.8) 76 (96.2) 75 (94.9)75 (94.9) Discontinued Study 3 (3.7) 7 (8.6) 5 (6.3) 3 (3.8) 4 (5.1) 4(5.1) Reasons for discontinuation from the study, n (% ^(b)) Safetyreasons (AEs) 1 (1.2) 1 (1.2) 2 (2.5) 0 1 (1.3) 1 (1.3) Investigator'srequest 0 0 0 0 0 0 Subject's request (not 1 (1.2) 3 (3.7) 2 (2.5) 1(1.3) 1 (1.3) 2 (2.5) AE) Noncompliance 0 0 0 0 1 (1.3) 0 Use ofconcomitant 0 1 (1.2) 0 0 0 1 (1.3) therapy Lost to follow-up 1 (1.2) 2(2.5) 1 (1.3) 1 (1.3) 0 0 (0.0) Other (not AE) 0 0 0 1 (1.3) 1 (1.3) 0AE = adverse event; IMIQ = Imiquimod ^(a) Includes subjects who completeboth the treatment periods and the post-treatment follow-up period. ^(b)Percentage of randomized population.

Subject demographics for each study are tabulated in Table 69, and thenumber of baseline AK lesions for each study are tabulated in Table 70.

TABLE 69 Demographic Summary - Two-Week Treatment Cycle Regimen Studies;ITT Population GW01-0702 GW01-0704 2.5% 3.75% 2.5% 3.75% IMIQ IMIQPlacebo IMIQ IMIQ Placebo (N = 81) (N = 81) (N = 80) (N = 79) (N = 79)(N = 79) Age in years Mean ± SD 63.7 ± 10.7 63.8 ± 11.1 63.6 ± 8.3 65.0± 10.3 65.3 ± 10.0 65.0 ± 9.5 Median 63.3 63.9 63.4 64.4 65.3 63.7Minimum, Maximum 43.8, 88.7 36.5, 89.8 42.7, 83.1 39.6, 90.0 36.3, 86.446.4, 89.1 Sex, n (%) Male 59 (72.8) 69 (85.2) 70 (87.5) 68 (86.1) 63(79.7) 60 (75.9) Female 22 (27.2) 12 (14.8) 10 (12.5) 11 (13.9) 16(20.3) 19 (24.1) Race, n (%) White 81 (100)  81 (100)  80 (100)  79(100)  79 (100)  78 (98.7) Non-White 0 0 0 0 0 1 (1.3) Ethnicity, n (%)Hispanic 4 (4.9) 5 (6.2) 5 (6.3) 0 1 (1.3) 0 Non-Hispanic 77 (95.1) 76(93.8) 75 (93.8) 79 (100)  78 (98.7) 79 (100)  Fitzpatrick skin type, n(%) I  9 (11.1) 5 (6.2) 6 (7.5) 20 (25.3) 17 (21.5) 13 (16.5) II 35(43.2) 43 (53.1) 25 (31.3) 27 (34.2) 31 (39.2) 33 (41.8) III 23 (28.4)17 (21.0) 37 (46.3) 20 (25.3) 26 (32.9) 26 (32.9) IV 11 (13.6) 15 (18.5)11 (13.8) 11 (13.9) 5 (6.3) 5 (6.3) V 3 (3.7) 1 (1.2) 1 (1.3) 1 (1.3) 02 (2.5) Location of Treatment Area, n (%) Face 61 (75.3) 66 (81.5) 60(75.0) 56 (70.9) 55 (69.9) 59 (74.7) Balding Scalp 20 (24.7) 15 (18.5)20 (25.0) 23 (29.1) 24 (30.4) 20 (25.3) SD = standard deviation; IMIQ =Imiquimod Fitzpatrick skin type: I = burns easily, never tans; II =burns easily, tans minimally with difficulty; III = burns moderately,tans moderately and uniformly; IV = burns minimally, tans moderately andevenly; V = rarely burns, tans profusely; VI = never burns, tansprofusely.

TABLE 70 Actinic Keratosis Lesions at Baseline - Two-Week TreatmentCycle Regimen Studies; ITT Population GW01-0702 GW01-0704 2.5% 3.75%2.5% 3.75% IMIQ IMIQ Placebo IMIQ IMIQ Placebo Baseline values (N = 81)(N = 81) (N = 80) (N = 79) (N = 79) (N = 79) Mean (SD) 11.11 (4.42)10.89 (4.90) 11.74 (4.77) 10.77 (4.44) 11.16 (4.81) 10.82 (4.64) Median10 9 10 10 11 10 Minimum, Maximum 5, 20 5, 20 5, 20 5, 20 5, 29 5, 20 Pvalue vs Placebo^(a) 0.376 0.256 NA 0.864 0.542 NA P value vs 3.75%0.818 NA NA 0.688 NA NA imiquimod cream^(a) SD = Standard deviation^(a)P values are from Cochran-Mantel-Haenszel test, are stratified byinvestigator center, taking 2 treatment groups at a time.

Subjects in studies GW01-0702 and GW01-0704 are compliant with theadministration of study medication; greater than 91% of the subjects arecompliant with the dosing regimen. Compliance is defined as applyingmore than 75% of the prescribed doses; ‘rest’ days are considered asapplication days.

Primary and secondary efficacy results for the GW01-0702 and GW01-0704studies are presented in Table 71, Table 72 and Table 73. The primaryefficacy variable is the rate of complete clearance at EOS (Week 14).The secondary efficacy variables are the rate of partial clearance (atleast 75% reduction in AKs from baseline) at EOS, and the percent changefrom Baseline to EOS in investigator counts of AK lesions. Both activetreatment arms demonstrate greater efficacy than placebo, which isstatistically significant for all primary and secondary endpoints.

TABLE 71 ITT (LOCF) Complete Clearance Rates at EOS for IndividualTwo-Week Treatment Cycle Regimen Studies Study 3.75% IMIQ 2.5% IMIQPlacebo GW01-0702 25.9% (21/81) 23.5% (19/81)  2.5% (2/80) GW01-070445.6% (36/79) 38.0% (30/79) 10.1% (8/79) Combined 35.6% (57/160) 30.6%(49/160)  6.3% (10/159)

TABLE 72 ITT (LOCF) Partial Clearance Rates at EOS for IndividualTwo-Week Treatment Cycle Regimen Studies Study 3.75% IMIQ 2.5% IMIQPlacebo GW01-0702 45.7% (37/81) 42.0% (34/81) 18.8% (15/80) GW01-070473.4% (58/79) 54.4% (43/79) 26.6% (21/79) Combined 59.4% (95/160) 48.1%(77/160) 22.6% (36/159)

TABLE 73 ITT (LOCF) Median Percent Change from Baseline in AK LesionCount at EOS for Individual Two-Week Treatment Cycle Regimen StudiesStudy 3.75% IMIQ 2.5% IMIQ Placebo GW01-0702 −72.7% −60.0% −21.1%GW01-0704 −90.9% −76.5% −30.0% Combined −81.8% −71.8% −25.0%

The incidence rates for selected safety parameters for the combinedTwo-Week Treatment Cycle Regimen studies are displayed in Table 74.

TABLE 74 Summary of Incidence Rates for Selected Safety Parameters(Combined Two-Week Treatment Cycle Regimen Studies) 3.75% IMIQ 2.5% IMIQPlacebo (N = 160) (N = 160) (N = 159) Discontinued study prematurely 2(1.3%) 1 (0.6%) 3 (1.9%) due to safety reasons, n (%) Treatment-relatedAEs, n (%) 31 (19.4%) 19 (11.9%) 4 (2.5%) Rest periods, n (%) 17 (10.6%)11 (6.9%)  0 (0%)  

The most common treatment-related adverse events are displayed in Table75 below.

TABLE 75 Incidence of Most Common* Treatment-Related Adverse Events(Combined Two-Week Treatment Cycle Regimen Studies) 3.75% IMIQ 2.5% IMIQPlacebo MedDRA Term (N = 160) (N = 160) (N = 159) Application sitepruritus 7 (4.4%) 6 (3.8%) 1 (0.6%) Application site pain 5 (3.1%) 2(1.3%) 0% Application site irritation 5 (3.1%) 4 (2.5%) 0% Fatigue 4(2.5%) 0% 0% Headache 4 (2.5%) 1 (0.6%) 2 (1.3%) Dizziness 3 (1.9%) 0%0% Lymphadenopathy 3 (1.9%) 3 (1.9%) 0% Nausea 3 (1.9%) 1 (0.6%) 0%Pyrexia 2 (1.3%) 0% 0% Application site swelling 2 (1.3%) 0% 0%Arthralgia 2 (1.3%) 0% 0% *>1% in the 3.75% imiquimod treatment group

For each of the two-week treatment cycle regimen studies, LSRs appear tobe dose-dependent. The combined AUC of LSR_(sum) Scores are 272, 242 and140 for the 3.75% imiquimod, 2.5% imiquimod, and placebo treatmentgroups, respectively. Erythema is the most intense LSR during thetreatment cycles, and on average all LSRs return to baseline at thefirst observation post-treatment cycle (within either two or four weeks,following cycles 1 and 2, respectively). The combined incidence ofsevere erythema is 26.3%, 14.4%, and 0% for the 3.75% imiquimod, 2.5%imiquimod, and placebo treatment groups, respectively.

There were 12 subjects with 15 serious adverse events reported in thetwo-week treatment cycle regimen studies, of which one of the seriousadverse events for one of the subjects is considered related totreatment (diarrhea with secondary nausea/fatigue reported in the 3.75%treatment group).

In the two-week treatment cycle regimen studies, both 2.5% and 3.75%imiquimod creams demonstrate substantial efficacy for the treatment ofAKs that is consistently significantly greater than that of placebocream, with a trend toward greater efficacy in the 3.75% group. Bothproducts are well-tolerated as evidence by measures of adverse events,ability of subjects to remain in the study, incidence of rest periods,and compliance with study regimen. Both active products result inincreases in local skin reactions versus the placebo cream. For bothactive creams, the LSRs rapidly reduces with the completion of eachtreatment cycle and these LSRs are associated with relatively fewreported application site reactions.

Studies of Three-Week Treatment Cycles

Preliminary data from the Three-Week Treatment Cycle Regimen Studies(GW01-0703 and GW01-0705) are presented as follows.

Subject Disposition for Studies GW01-0703 and GW01-0705 is tabulated inTable 76.

TABLE 76 Subject Disposition; Three-Week Treatment Cycle Regimen StudiesGW01-0703 GW01-0705 2.5% 3.75% 2.5% 3.75% IMIQ IMIQ Placebo IMIQ IMIQPlacebo Total no. of subjects, n (%) Randomized 82  80  78  82  82  86 Completed Study ^(a) 77 (93.9) 76 (95.0) 73 (93.6) 80 (97.6) 76 (92.7)81 (94.2) Discontinued Study 5 (6.1) 4 (5.0) 5 (6.4) 2 (2.4) 6 (7.3) 5(5.8) Reasons for discontinuation from the study, n (% ^(b)) Safetyreasons (AEs) 1 (1.2) 2 (2.5) 0 1 (1.2) 2 (2.4) 1 (1.2) Investigator'srequest 0 0 0 0 0 0 Subject's request (not AE) 3 (3.7) 2 (2.5) 4 (5.1) 02 (2.4) 0 Noncompliance 1 (1.2) 0 (0.0) 0 (0.0) 0 0 0 Use of concomitanttherapy 0 0 0 0 0 0 Lost to follow-up 0 0 0 0 (0.0) 1 (1.2) 1 (1.2)Other (not AE) 0 (0.0) 0 (0.0) 1 (1.3) 1 (1.2) 1 (1.2) 3 (3.5) AE =adverse event; IMIQ = Imiquimod ^(a) Includes subjects who complete boththe treatment periods and the post-treatment follow-up period. ^(b)Percentage of randomized population.

Subject demographics for each study are tabulated in Table 77, and thenumber of baseline AK lesions for each study are tabulated in Table 78.

TABLE 77 Demographic Summary - Three-Week Treatment Cycle RegimenStudies; ITT Population GW01-0703 GW01-0705 2.5% 3.75% 2.5% 3.75% IMIQIMIQ Placebo IMIQ IMIQ Placebo (N = 82) (N = 80) (N = 78) (N = 82) (N =82) (N = 86) Age in years Mean ± SD 65.7 ± 10.4 64.5 ± 10.8 63.0 ± 10.166.4 ± 10.0 64.1 ± 9.7 64.4 ± 11.5 Median 66.7 64.0 63.6 65.9 63.7 65.8Minimum, 85.3, 3.3, 40.3, 85.5 39.8, 83.8 45.4, 87.3 90.9, 41.6 37.9,87.0 Maximum Sex, n (%) Male 62 (75.6) 63 (78.8) 63 (80.8) 66 (80.5) 60(73.2) 72 (83.7) Female 20 (24.4) 17 (21.3) 15 (19.2) 16 (19.5) 22(26.8) 14 (16.3) Race, n (%) White 82 (100)  78 (97.5) 77 (98.7)  82(100.0)  82 (100.0)  86 (100.0) Non-White 0  2 (2.5) 1 (1.3) 0  0  0 Ethnicity, n (%) Hispanic 2 (2.4) 1 (1.3) 0 (0.0) 6 (7.3) 6 (7.3) 6(7.0) Non-Hispanic 80 (97.6) 79 (98.8) 78 (100)  76 (92.7) 76 (92.7) 80(93.0) Fitzpatrick skin type, n (%) I 8 (9.8) 11 (13.8) 11 (14.1) 12(14.6) 11 (13.4) 12 (14.0) II 35 (42.7) 31 (38.8) 28 (35.9) 28 (34.1) 47(57.3) 39 (45.3) III 28 (34.1) 24 (30.0) 26 (33.3) 33 (40.2) 21 (25.6)23 (26.7) IV  9 (11.0) 13 (16.3) 10 (12.8) 8 (9.8) 3 (3.7)  9 (10.5) V 2(2.4) 1 (1.3) 3 (3.8) 1 (1.2) 0  3 (3.5) Location of Treatment Area, n(%) Face 63 (76.8) 54 (67.5) 60 (76.9) 52 (63.4) 61 (74.4) 62 (72.1)Balding Scalp 19 (23.2) 26 (32.5) 18 (23.1) 30 (36.6) 21 (25.6) 24(27.9) SD = standard deviation; IMIQ = Imiquimod Fitzpatrick skin type:I = burns easily, never tans; II = burns easily, tans minimally withdifficulty; III = burns moderately, tans moderately and uniformly; IV =burns minimally, tans moderately and evenly; V = rarely burns, tansprofusely; VI = never burns, tans profusely.

TABLE 78 Actinic Keratosis Lesions at Baseline - Three-Week TreatmentCycle Regimen Studies; ITT Population GW01-0703 GW01-0705 2.5% 3.75%2.5% 3.75% IMIQ IMIQ Placebo IMIQ IMIQ Placebo Baseline values (N = 82)(N = 80) (N = 78) (N = 82) (N = 82) (N = 86) Mean (SD) 10.74 (4.45)11.99 (5.47) 11.24 (4.70) 10.43 (4.05) 10.26 (4.12) 9.49 (3.67) Median10 11 10 9 9 8 Minimum, Maximum 5, 20 5, 23 5, 20 5, 20 5, 20 5, 20 Pvalue vs Placebo^(a) 0.408 0.359 NA 0.094 0.197 NA P value vs 3.75%0.113 NA NA 0.776 NA NA imiquimod cream^(a) SD = Standard deviation^(a)P values are from Cochran-Mantel-Haenszel test, stratified byinvestigator center, taking 2 treatment groups at a time.

Subjects in studies GW01-0703 and GW01-0705 are compliant with theadministration of study medication; greater than 92% of the subjects arecompliant with the dosing regimen. Compliance is defined as applyingmore than 75% of the prescribed doses; ‘rest’ days are considered asapplication days.

Primary and secondary efficacy results for the GW01-0703 and GW01-0705studies are presented in Table 79, Table 80, and Table 81. The primaryefficacy variable is the rate of complete clearance at EOS (Week 17).The secondary efficacy variables are the rate of partial clearance (atleast 75% reduction in AKs from baseline) at EOS, and the percent changefrom Baseline to EOS in investigator counts of AK lesions. Both activetreatment arms demonstrate greater efficacy than placebo, which isstatistically significant for all primary and secondary endpoints.

TABLE 79 ITT (LOCF) Complete Clearance Rates at EOS for IndividualThree-Week Treatment Cycle Regimen Studies Study 3.75% IMIQ 2.5% IMIQPlacebo GW01-0703 32.5% (26/80) 23.2% (19/82) 5.1% (4/78) GW01-070535.4% (29/82) 26.8% (22/82) 5.8% (5/86) Combined 34.0% (55/162)   25%(41/164) 5.5% (9/164)

TABLE 80 ITT (LOCF) Partial Clearance Rates at EOS for IndividualThree-Week Treatment Cycle Regimen Studies Study 3.75% IMIQ 2.5% IMIQPlacebo GW01-0703 56.3% (45/80) 46.3% (38/82) 11.5% (9/78) GW01-070551.2% (42/82) 39.0% (32/82) 14.0% (12/86) Combined 53.7% (87/162) 42.7%(70/164) 12.8% (21/164)

TABLE 81 ITT (LOCF) Median Percent Change from Baseline in AK LesionCount at EOS for Individual Three-Week Treatment Cycle Regimen StudiesStudy 3.75% IMIQ 2.5% IMIQ Placebo GW01-0703 −82.3% −66.7% −23.6%GW01-0705 −78.9% −66.7% −22.5% Combined −80.0% −66.7% −23.6%

The incidence rates for selected safety parameters for the combinedthree-week treatment cycle regimen studies are displayed in Table 82.

TABLE 82 Summary of Incidence Rates for Selected Safety Parameters(Combined Three-Week Treatment Cycle Regimen Studies) 3.75% IMIQ 2.5%IMIQ Placebo (N = 162) (N = 164) (N = 164) Discontinued studyprematurely 4 (2.5%) 2 (1.2%) 1 (0.6%) due to safety reasons, n (%)Treatment-related AEs, n (%) 60 (37.0%) 44 (26.8%) 4 (2.4%) Restperiods, n (%) 44 (27.2%) 28 (17.1%) 0 (0%)  

The most common treatment-related adverse events are displayed in Table83.

TABLE 83 Incidence of Most Common* Treatment-Related Adverse EventsCombined Three-Week Treatment Cycle Regimen Studies) 3.75% IMIQ 2.5%IMIQ Placebo MedDRA Term (N = 162) (N = 164) (N = 164) Application sitepain 15 (9.3%)  11 (6.7%)  0% Application site pruritus 14 (8.6%)  12(7.3%)  1 (0.6%) Influenza like illness 12 (7.4%)  6 (3.7%) 0%Application site irritation 9 (5.6%) 6 (3.7%) 1 (0.6%) Fatigue 7 (4.3%)5 (3.0%) 0% Application site bleeding 5 (3.1%) 2 (1.2%) 0%Lymphadenopathy 5 (3.1%) 4 (2.4%) 0% Pyrexia 5 (3.1%) 0% 0% Headache 4(2.5%) 4 (2.4%) 0% Cheilitis 3 (1.9%) 1 (0.6%) 1 (0.6%) Myalgia 3 (1.9%)0% 0% Application site discomfort 2 (1.2%) 0% 0% Application siteerythema 2 (1.2%) 0% 0% Chills 2 (1.2%) 1 (0.6%) 0% Dysphonia 2 (1.2%)0% 0% Herpes simplex 2 (1.2%) 2 (1.2%) 0% Herpes zoster 2 (1.2%) 0% 0%Lethargy 2 (1.2%) 0% 0% Nausea 2 (1.2%) 1 (0.6%) 0% *>1% in the 3.75%imiquimod treatment group

For each of the three-week treatment cycle regimen studies, LSRs appearto be dose-dependent. The combined AUC of LSR. Scores are 413, 372 and189 for the 3.75% imiquimod, 2.5% imiquimod, and placebo treatmentgroups, respectively. Erythema is the most intense LSR during thetreatment cycles, and on average all LSRs return to baseline at thefirst observation post-treatment cycle. The combined incidence of severeerythema is 44.7%, 28.2%, and 0% for the 3.75% imiquimod, 2.5%imiquimod, and placebo treatment groups, respectively.

There are 13 subjects who report 18 serious adverse events in theThree-Week Treatment Cycle Regimen studies; one of these serious adverseevents is considered related to treatment (pancytopenia reported in the3.75% treatment group; note that this subject had a previous history ofpancytopenia).

In the Three-Week Treatment Cycle Regimen studies, both 2.5% and 3.75%imiquimod creams demonstrate substantial efficacy for the treatment ofAKs that is consistently significantly greater than that of placebocream, with a trend toward greater efficacy with the higherconcentration cream. Discontinuation rates for any cause, as well as forsafety reasons are low in all treatment groups, and as such, bothimiquimod creams can be considered ‘well-tolerated’. However, a largernumber of subjects that are treated with either the 2.5% or 3.75%imiquimod creams require rest periods from the intended two 3-weektreatment cycles. Rest periods and other measures of treatmenttolerability (related adverse events, application site reactions, LSRs)demonstrate a dose dependent effect, with the highest incidences in the3.75% 3-week cycle treatment group.

Selection of the optimal dose/regimen for submission for marketingapproval requires the comparisons of both the benefits and risks foreach of each dose/regimen combinations that are studied. StudiesGW01-0702 and GW01-0704 are duplicate studies investigating two 2-weektreatment cycles (aka two-week treatment cycle regimen studies); andstudies GW01-0703 and GW01-0705 are duplicate studies investigating two3-week treatment cycles (aka three-week treatment cycle regimenstudies). Data from the four Phase 3 studies are combined as identicalpairs (GW01-0702/GW01-0704 and GW01-0703/GW01-0705).

Identical pairs of studies, each including 3 treatment groups, areconsidered in the analysis of dose/regimen selection:

Two-Week Treatment Cycle Regimen (Studies GW01-0702 and GW01-0704)

-   -   3.75% imiquimod    -   2.5% imiquimod    -   Placebo

Three-Week Treatment Cycle Regimen (Studies GW01-0703 and GW01-0705)

-   -   3.75% imiquimod    -   2.5% imiquimod    -   Placebo

To examine the impact of drug concentrations on efficacy, the fourimiquimod treatment groups (2.5% and 3.75%, 2-week and 3-week regimens)can be combined by concentration, irrespective of treatment regimen.Data for 2.5% imiquimod (both 2 and 3-Week Treatment Cycle Groups)versus that of 3.75% imiquimod (both 2 and 3-Week Treatment CycleGroups) are evaluated for efficacy effects of concentration (refer toTable 84 below). Preliminary evaluation suggests an effect of drugconcentration in favor of the 3.75% concentration for all three efficacyendpoints: Complete Clearance, Partial Clearance, and Percent Reductionfrom Baseline of AK lesions. Preliminary evaluation suggests that thetwo regimens (2-week and 3-week treatment cycles) are comparable interms of the efficacy endpoints. In addition, all four dosing regimensthat are used show statistically and clinically significanteffectiveness in the reduction of AK lesions in the target population.

TABLE 84 Analysis of Primary and Secondary Efficacy Endpoints (CombinedStudies) 2-Week Cycle Regimen 3-Week Cycle Regimen Parameter 3.75% 2.5%Placebo 3.75% 2.5% Placebo Complete Clearance at EOS n/N, (%) 57/160(35.6) 49/160 (30.6) 10/159 (6.3)  55/162 (34.0) 41/164 (25.0) 9/164(5.5) 95% 28.2, 43.6 23.6, 38.4 3.1, 11.3 26.7, 41.8 18.6, 32.3 2.5,10.2 confidence interval Partial Clearance at EOS n/N, (%) 95/160 (59.4)77/160 (48.1) 36/159 (22.6) 87/162 (53.7) 70/164 (42.7) 21/164 (12.8)95% 51.3, 67.1 40.2, 56.2 16.4, 29.9  45.7, 61.6 35.0, 50.6 8.1, 18.9confidence interval Percent Change in Number of AK Lesions from Baselineto EOS N 160 160 159 162 164 164 Median −81.8 −71.8 −25.0 −80.0 −66.7−23.6 Mean (SD)  −68.7 (43.4)  −59.2 (41.6)  −27.6 (52.1)  −64.3 (43.0) −57.0 (45.4)  −24.5 (47.0) 95% −75.4, 61.9  −65.7, 52.7  −35.7, 19.4−71.0, 57.7  −64.0, −50.0 −31.7, 17.2  confidence interval

As indicated herein, the efficacy results for the two 2-cycle treatmentregimens, i.e., the 2×2×2 weeks and 3×3×3 weeks treatment cycles,suggest that the additional doses provided in the 3-week treatment cycleregimen results in no additional efficacy over that shown for the 2-weektreatment cycle regimen. This finding is consistent with the rank orderperformance of the 3.75% product for all efficacy endpoints in all fourindividual Phase 3 studies. Therefore, from an efficacy standpoint, the3.75% imiquimod cream, when applied daily in two 2-week treatmentcycles, is believed to be the preferred dose and regimen combination totreat actinic keratosis.

Safety for all four dose regimens is also considered. Since the longer3-week treatment regimen (with its greater drug exposure) shows noadditional efficacy, it is believed that a choice of a 3-week regimenshould be based on an improved safety profile.

As with efficacy, safety data are examined from the pooled identicalstudies (GW01-0702/GW01-0704 and GW01-0703/GW01-0705).

Key safety outcomes are presented above and included:

Incidence of Discontinuation from Study

Incidence of Discontinuation from Study due to Safety Reasons (AEs)

Incidence of Rest Periods

Incidence of Treatment-Related AEs

AUC of LSRsum scores

With the exception of LSRs (which are investigator assessed ‘signs’),these measures address symptoms that are experienced by the subject orinvestigator actions that are related to subject safety (i.e.,discontinuations, rest periods, adverse events including LSRs requiringmedical intervention).

As can be seen in Table 85 below, discontinuation rates from the fourPhase 3 studies for all causes (including safety) are low across alltreatment groups, thus supporting the overall tolerability of all doseregimens. Inspection of the incidence rates for Rest Periods andTreatment-Related AEs suggests that the 3-week Treatment Cycle Regimensare relatively less well-tolerated than both 2-week Treatment CycleRegimens.

TABLE 85 Selected Safety Parameters (Combined Studies) Combined Two-WeekTreatment Combined Three-Week Treatment Cycle Regimen Studies CycleRegimen Studies 3.75% 3.75% IMIQ 2.5% IMIQ Placebo IMIQ 2.5% IMIQPlacebo (N = 160) (N = 160) (N = 159) (N = 162) (N = 164) (N = 164)Discontinued study 11 (6.9%)  6 (3.8%) 9 (5.7%) 10 (6.2%)  7 (4.3%) 10(6.1%)  prematurely (any reason) Discontinued study 2 (1.3%) 1 (0.6%) 3(1.9%) 4 (2.5%) 2 (1.2%) 1 (0.6%) prematurely due to safety reasons, n(%) Treatment-related AEs, n 31 (19.4%) 19 (11.9%) 4 (2.5%) 60 (37.0%)44 (26.8%) 4 (2.4%) (%) Rest periods, n (%) 17 (10.6%) 11 (6.9%)  0(0%)   44 (27.2%) 28 (17.1%) 0 (0%)  

For the 2-week treatment cycle regimen, the 2.5% and 3.75% imiquimodcreams show similar tolerability. Although the overall incidences oftreatment-related adverse events for the 2-week Treatment Cycle Regimensshow a dose-related trend (see above 85), the most commontreatment-related AEs are application site reactions (see Tables 75 and83). Inspection of the individual treatment-related AEs reveals lowrates for all the individual terms, irrespective of dose group. AEs thatmay reflect systemic pharmacologic effects of imiquimod's activation ofcytokines (e.g., fatigue) are reported; however, systemic AEs occur at alow rate.

Additional to the adverse event data above, the physical signs ofanticipated local skin reactions (LSRs) are rated by the investigatorsvia six assessments scores at each study visit. The assessments scoresare summated and then integrated across the study duration as AUC ofLSR_(sum) scores. The AUC of LSR_(sum) scores for all four treatmentgroups are presented in Table 86.

TABLE 86 Summary of AUC of LSR_(sum) Scores (Combined Across Studies)3.75% IMIQ 2.5% IMIQ Placebo Combined Two-Week Treatment 272 242 140Cycle Regimen Studies Combined Three-Week Treatment 413 372 189 CycleRegimen Studies

The difference in AUC of LSR_(sum) scores by treatment regimen isremarkable. Note that the scores for the 3-week cycle treatment cycleregimens (including placebo) reflect the longer dosing and studyduration associated with those study designs. Nonetheless, the datashows pronounced increases in AUC of LSR_(sum) scores for both doses inthe 3-week cycle treatment groups. Scores for both of the 2-week cycletreatment groups are lower than the 3-week treatment cycle regimens,with a relatively small increase in the 3.75% AUC of LSR_(sum) scorecompared to the 2.5% imiquimod treatment group for the 2-week treatmentcycle regimen studies.

Looking across the safety parameters, it appears that the short 2-weekTreatment Cycle Regimen is relatively better tolerated than the 3-weekTreatment Cycle Regimen. Within the 2-week cycle Treatment Cycle Regimenboth doses are well-tolerated, although safety incidence rates andscores appear to slightly favor the 2.5% concentration.

As discussed, the 3-week Treatment Cycle Regimens, irrespective ofproduct concentration, demonstrates a less favorable safety profileversus the 2-week Treatment Cycle Regimens with no offsetting efficacybenefit. Within the 2-week Treatment Cycle Regimen studies, the 2.5%imiquimod formulation appear to have a slightly improved safety profileto the 3.75% product, though both products are well-tolerated. However,the 3.75% product shows a consistent incremental efficacy benefit to the2.5% product.

In the primary ITT efficacy analysis, missing observations due to earlydiscontinuation are imputed using the last observation carried forward(LOCF). Baseline data are carried forward if no post-Baseline dataexisted for the subject. The sensitivity of the primary outcome toimputation methods is explored in each of the separate clinical studyreports, and the results are found to be robust with respect to changesin imputation methodology. The results of the PP analysis are also foundto be entirely consistent with those of the ITT analysis.

Wherever the investigator reported AK lesion count as “indeterminate,”the subject is considered not cleared (and not partially cleared), butthe numerical lesion count is taken as a missing value.

The demographic and background characteristics of the efficacy studypopulations by treatment group in all 4 Phase 3 studies are combined byidentical study design in pairs (i.e., GW01-0702 and GW01-0704 will becombined in one pair and GW01-0703 and GW01-0705 will be combined in asecond pair). The number and percentage by treatment group and overallare presented for subjects randomized, subjects included in the ITTpopulation, subjects completing the study, and subjects discontinuingthe study, overall and by reason for discontinuation.

Subject age, height, weight, and Baseline lesion count is summarized bymean, standard deviation, median, and range by treatment group. Sex,race, ethnicity, Fitzpatrick skin type, location of treatment area (faceor balding scalp), and prior AK treatment history is characterized byfrequency distribution by treatment group.

Descriptive statistics (mean, standard deviation, median, and range) isused to summarize product usage and exposure for the ITT populations bytreatment group. Measures of study medication exposure, for eachtreatment cycle and overall, includes the total duration of treatment(date of last dose minus date of first dose plus 1, excluding theno-treatment period), the total number of applications, the total numberof packets used, the total amount of active drug applied, and theaverage number of packets used per application. The number andpercentage of subjects by treatment group who make fewer than 75% of therequired applications (fewer than 21 applications and/or rest days inthe 2-week treatment cycle regimen, and fewer than 32 applicationsand/or rest days in the 3-week treatment cycle regimen) is reported.

The primary efficacy variable prospectively defined for all studies issubject status with respect to complete clearance of AK lesions at Endof Study. This is defined as the absence of clinically visible orpalpable AK lesions in the treatment area.

Secondary efficacy variables are:

-   -   Subject status with respect to partial clearance of AK lesions        at End of Study, defined as at least a 75% reduction in the        number of AK lesions in the treatment area compared with        Baseline.    -   Percent change from Baseline to End of Study in investigator        counts of AK lesions.

The comparative and integrated analysis of efficacy focuses on theprimary and two secondary efficacy variables. Integrated and comparativesummaries is presented at the primary time point of End of Study. Thestudies are reviewed separately as well as with the identical studiescombined in pairs: GW01-0702 and GW01-0704 for the 2-week treatmentcycle regimen, and GW01-0703 and GW01-0705 for the 3-week treatmentcycle regimen.

In the planned statistical analyses defined prospectively and presented,all pairwise comparisons of active treatment versus placebo are madeusing Hochberg's modified Bonferroni procedure. If either test issignificant at a 0.025 level of significance, then that test isconsidered significant. Otherwise, if both tests are significant at0.05, then both tests are considered significant. The 3.75% and 2.5%treatment groups are compared to each other at the 0.05 level ofsignificance if at least one of these treatment groups is found to bedifferent than the placebo using the Hochberg test.

In this way, complete clearance rates, partial clearance rates, changefrom Baseline AK lesion counts, and percent change from Baseline AKlesion counts are analyzed using Cochran-Mantel-Haenszel (CMH)statistics, stratifying on site.

In the primary analysis of complete clearance rate, the Breslow-Daystatistic is tested at the 10% level for heterogeneity of the oddsratios across analysis sites. There are no findings of statisticalsignificance in these tests for any of the studies.

In order to characterize and explore the efficacy of the proposed drugproduct in subpopulations of interest, the data from the two pivotalstudies is combined and analyzed by age, sex, Fitzpatrick skin type,treatment area, and baseline lesion count. In each case, the ITTpopulation is divided into two subpopulations based on the specificcovariate of interest. For age, the subpopulations are selected as lessthan, or greater than or equal to, 65 years old. For skin type andbaseline lesion count, the subpopulations are selected as above or belowthe approximate median value of the covariate (combining I with II, andcombining III, IV, V, and VI) for skin type; taking less than or equalto 10 vs greater than 10 for baseline lesion count). P values forcomplete clearance and partial clearance are computed using ageneralized linear model (PROC GENMOD) assuming a multinomialdistribution (DIST=MULT) and a cumulative login link function(LINK=CLOGIT) including effects of treatment, subpopulation, andinteraction. P values for percent reduction are derived from theanalysis of variance (PROC GLM) including effects of treatment,subpopulation, and interaction. A similar analysis is presented for thesubpopulation of subjects who showed increased AK lesion count at anytime after baseline. This subpopulation is characterized in currentAldara® labeling as having had “sub-clinical lesions”. In these fourstudies, it is seen that the great majority of subjects are included inthis subpopulation.

The LSR intensities are summarized in each study by frequency counts andmean score by treatment group and study visit for each LSR type:

-   -   Erythema (0=None, 1=Faint to mild redness, 2=Moderate redness,        3=Intense redness),    -   Edema (0=None, 1=Mild visible or barely palpable        swelling/induration, 2=Easily palpable swelling/induration,        3=Gross swelling/induration),    -   Weeping/Exudate (0=None, 1=Minimal exudate, 2=Moderate exudate,        3=Heavy exudate),    -   Flaking/Scaling/Dryness (0=None, 1=Mild dryness/flaking,        2=Moderate dryness/flaking, 3=S evere dryness/flaking),    -   Scabbing/Crusting (0=None, 1=Crusting, 2=Serous scab, 3=Eschar),    -   Erosion/Ulceration (0=None, 1=Erosion, 2=Ulceration).

The most intense reaction (post-baseline) for each type is alsopresented by frequency distribution and mean score by treatment group.

An LSR sum score is computed at each study visit (addition of sixscores). Three areas under the curve (AUC, in days, using thetrapezoidal approximation) are calculated for each subject: fromBaseline to beginning of Treatment Cycle 2, from beginning of TreatmentCycle 2 to End of Study, and from Baseline to End of Study. These valuesare compared pair wise between treatment groups using Fisher's leastsignificant differences in the one-way analysis of variance (treatmentgroup). Discontinued subjects are included in this analysis using LOCF.Details of the calculation of AUC are provided in the clinical studyreports.

A pooled analysis of is also provided, with P values derived from theanalysis of variance (PROC GLM) including effects of concentration,regimen, and interaction. When calculating the AUC over the course ofthe study period, it is noted that studies GW01-0702 and GW01-0704 are14 weeks in duration, while GW01-0703 and GW01-0705 are 17 weeks induration. The additional three weeks in the AUC for the GW01-0703 andGW01-0705 studies correspond to two additional weeks of treatment andone additional week in the no-treatment period between treatment cycles.Nonetheless, subjects in all four studies are followed through eightweeks after the last treatment application in order to allow completehealing of local skin reactions. Thus, the comparison of AUC LSR betweenthe 14-week studies and the 17-week studies, without adjustment, allowsan evaluation of the relative duration, as well as the severity of localskin reactions resulting from each of the four dosing regimens.

The number and percentage of subjects by treatment group combiningGW01-0702 with GW01-0704 and GW01-0703 with GW01-0705 is presented foreach of the following safety indicators.

Requiring Rest Period

Discontinuing the Study Prematurely for Any Reason

Discontinuing the Study Prematurely for Safety Reasons

Any Adverse Event

Any Treatment-Related Event

Any Application Site Reaction

Any Serious Adverse Event

Any Severe Adverse Event

The incidence of subjects requiring rest periods is calculated for eachtreatment group by Cycle 1, Cycle 2 and Overall.

Adverse events (AEs) is coded using MedDRA (Version 11) terminology.Treatment-emergent AEs is summarized for each treatment group (with thefour Phase 3 studies combined in pairs) by:

-   -   n (%) of Subjects in Decreasing Order of Incidence in the 3.75%        2-Week Treatment Cycle Group, Adverse Events with Incidence >1%        in the 3.75% 2-Week Treatment Cycle Group;    -   n (%) of Subjects in Decreasing Order of Incidence in the 3.75%        2-Week Treatment Cycle Group, Adverse Events Considered        Treatment-related by the Investigator;    -   n (%) of Subjects in Decreasing Order of Incidence in the 3.75%        2-Week Treatment Cycle Group, Adverse Events Rated Severe;    -   n (%) of Subjects in Decreasing Order of Incidence in the 3.75%        2-Week Treatment Cycle Group, All Application Site Reactions.

The incidence of adverse events is summarized by gender, by agesubgroup, by skin type, by baseline lesion count, and by location oftreatment area (face or balding scalp). For age, the subpopulations isselected as less than or greater than or equal to, 65 years old. Forskin type and baseline lesion count, the subpopulations is selected asabove or below the approximate median value of the covariate (combiningI with II, and combining III, IV, V, and VI for skin type; taking lessthan or equal to 10 vs greater than 10 for baseline lesion count).

Serious AEs and AEs which led to the discontinuation of the subject fromthe study is listed by subject.

The frequency counts of shifts in alert status (normal to high, low tonormal, etc.) from Screening to End of Study is tabulated by treatmentgroup for each laboratory parameter combining the four Phase 3 studiesin pairs.

Example 25 An Open Label, Single Center, Non-Randomized Pharmacokinetic(PK) Study

An open label, single center, non-randomized pharmacokinetic (PK) studyin adult subjects diagnosed with actinic keratosis (“AK”) is conducted.This PK study is designed to quantify the pharmacokinetic profile ofimiquimod and its metabolites following 3 weeks (21 days) of dailyapplications of a 3.75% imiquimod formulation of Example in adultsubjects diagnosed with actinic keratosis (AK). The study is conductedunder maximal use conditions (dose, duration, disease severity, andapplication areas) in a population that had at least 10 AK lesions inthe application area. The application area is the entire face (exclusiveof nares, vermilion, periocular areas and ears) and/or the entirebalding scalp; areas estimated as approximately 200 cm². If the area ofthe entire balding scalp is less than 200 cm², the forehead area isincluded in order for the entire treatment area to be approximately 200cm². The daily dose is 2 packets of 3.75% imiquimod cream for threecontinuous weeks.

Thus, this PK study is conducted under maximal use conditions: (1) atleast 10 clinically typical visible or palpable AK lesions within thetreatment area (balding scalp or face); (2) application of 2 fullpackets (250 mg of formulation per packet) of 3.75% imiquimodformulation once daily for 21 days (maximal dosing regimen); and (3) askin area of approximately 200 cm² of the entire face or balding scalp(maximal treatment area).

Subjects stay at the study center overnight at treatment initiation (Day1, 1st dose), and end of treatment (Day 21, last dose) visits forcollection of a 24-hour serum PK profile. During the domicile periods ofinitiation (Day 1), and end of treatment (Day 20-21) visits, serum PKsamples are collected predose and at planned time points through 24hours post dose. At the end of treatment (Day 21), additional PK samplesare taken at approximately 48 and 72 hours post application. Singleserum samples for PK analyses of trough concentrations are obtained atDay 7 and Day 14 (in the morning prior to dosing).

Adverse events, study medication accountability, and dosing complianceare reviewed at each visit. Routine clinical laboratory assessments(serum chemistry, hematology and urinalysis) are performed at Screening,Day 1 (predose), and the end of study visits.

Nineteen subjects (14 males/5 females) are enrolled into the study and18 completed. One female subject discontinues the study prematurely dueto concurrent adverse events (moderate body aches and moderate fatigue),and therefore does not have a PK profile at Day 21 (steady-state). Forthe 19 enrolled subjects, 15 subjects apply the study medication to theentire face, and the remainder apply the study medication to the baldingscalp (which may include the upper face if <200 cm²).

A total of 19 subjects have pharmacokinetic profiles (sampling over 24hours) following the first dose, and 18 subjects have pharmacokineticprofiles (sampling over 72 hours) on Day 21. One subject misses a doseon Day 20, and therefore is excluded from the Day 21 analysis (17subjects have adequate data for Day 21 analyses of AUC0-24, Cmax andTmax). Trough serum concentrations are obtained on Days 7, 14, 21, and22. The trough concentrations on Days 7 and 14 are obtained duringoutpatient treatment while the trough concentrations on Days 21 and 22are obtained while the subjects are dosed in the clinical researchfacility. Trough imiquimod concentrations are summarized in Table 87.

TABLE 87 Summary of Imiquimod Trough Concentrations (ng/mL); Subjectswith Paired, Non-zero Data Geometric Geometric Geometric LS Mean LS MeanMean 90% Confidence N Test Reference Ratio Interval Day 14/7 15 0.13910.1277 1.0888 (0.7933-1.4946) Day 21/14 16 0.1791 0.1344 1.3328(0.9193-1.9325) Day 22/21 16 0.1671 0.1791 0.9331 (0.6612-1.3169)

Serum concentrations of imiquimod are relatively low in subjects treatedwith daily applications of an imiquimod 3.75% cream of Example 23 for upto 21 days. While serum concentrations of two imiquimod metabolites (S26704 and S 27700 combined) are measured throughout the study, very fewsamples had concentrations above the lower limit of quantitation (LLOQ).Therefore, these data are too sparse to assess.

The ratio of trough concentrations is examined to determine whethersteady-state conditions are achieved during 21 days of topical treatmentwith 3.75% imiquimod cream. Under steady-state treatment conditions, thetrough concentrations, aside from variability, demonstrate a stableplateau value (i.e., not significantly increasing over time, asindicated by a ratio significantly >1). Considering the variability inimiquimod trough concentrations (observed CV % ranged from 47.6-58.0%),a ratio<1.43 (following log transformation) is pre-selected to indicatethe achievement of steady state; all three ratios meet that criterion.This analysis of trough ratios (i.e., using only those subjects withpaired, non-zero data) is also confirmed by an analysis which includesall subjects with paired data by replacing the zero (BQL) values with0.025 ng/mL (½ of the LLOQ).

The single-dose and steady-state pharmacokinetic parameters for dailyapplication of 3.75% imiquimod cream are summarized in Table 88 andTable 89.

TABLE 88 Preliminary Steady-State (Day 21) Imiquimod PharmacokineticVariables AUC₀₋₂₄ Cmax Tmax λz T½ (ng · hr/mL) (ng/mL) (hr) (hr⁻¹) (hr)N 17 17 17 15 15 Geometric Mean 5.029 0.274 6.623 0.027 26.11 Mean 5.9740.323 7.356 0.029 29.26 SD 3.088 0.159 3.500 0.014 16.98 CV % 51.7%49.2% 47.6% 48.5% 58.0% Median 7.019 0.350 9 0.0271 25.56 Min 1.1390.069 4 0.0082 9.72 Max 11.800 0.588 16 0.0713 84.06

TABLE 89 Single-dose and Steady-state Pharmacokinetics of 3.75%Imiquimod Cream of Example 23 (Study GW01-0706) Mean (SD) ParameterN^(c) Day 1 N^(d) Day 21 C_(max) (ng/mL) 17 0.136 (0.059) 17 0.323(0.159) C_(min) (ng/mL)^(a) — NA 17 0.199 (0.109) T_(max) (hr)^(b) 17    9.0 (4.0-24.03) 17     9.0 (4.0-16.0) AUC₀₋₂₄ 17 1.831 (0.889) 175.974 (3.088) (ng · hr/mL) AUC_(0-t) 17 1.679 (1.056) — NA (ng · hr/mL)AUC_(0-inf) 11 4.443 (1.309) — NA (ng · hr/mL) λ_(z) (1/hr) 11 0.0450(0.0219) 15 0.0294 (0.0142) T_(1/2) (hr) 10 19.818 (10.125) 15 29.260(16.979) R_(AUC) — NA 15 3.873 (2.153) R_(Cmax) — NA 15 2.810 (1.514)λ_(zEFF) (hr⁻¹) — NA 15 0.0235 (0.0229) T_(1/2EFF) (hr) — NA 15 55.339(36.380) NA = Not applicable ^(a)Pre-dose concentration (t = 0)^(b)Median (minimum-maximum) ^(c)Subjects 001-601 and 001-618 were BLQ,therefore unable to calculate PK parameters ^(d)Subject 001-619 did nothave concentration data on Day 21; Subject 001-608 excluded due tomissed dose on Day 20

Peak exposure (C_(max)) and total exposure (AUC₀ ₂₄) for imiquimod arehigher on Day 21 than Day 1 when analyzing all subjects in thepharmacokinetic population. The mean accumulation ratios, RC_(max) andR_(AUC), for all subjects in the pharmacokinetic population are about2.810 and about 3.873, respectively. The serum concentration profile onDay 21 is relatively flat across the dosage interval, and mean C_(max)(0.323±0.159 ng/mL) is less than twice the level of mean C_(min)(0.199±0.109 ng/mL). The mean effective half life for accumulation isabout 55.3 hours and the mean observed elimination half life is about29.3 hours on Day 21. Analysis of trough concentrations over timeindicate that steady state conditions are achieved between Day 7 and Day14, which is consistent with the time to steady state that is predictedfrom observed elimination half life (approximately 6 days) and theeffective half life for accumulation (approximately 12 days).

In a comparison of female and male subjects who apply an imiquimod 3.75%cream of Example 23 to the face, serum pharmacokinetics for imiquimodare very similar for both groups on Day 21. In a comparison of scalp andface applications in male subjects, imiquimod C_(max) and AUC₀ ₂₄ arelower on Day 21 in subjects who apply study medication to balding scalprather than to the face. Analyses of the subgroups are limited by widevariability in the data, small overall numbers, and a large disparity ingroup sizes (female/male comparison of 4 versus 10 subjects, andscalp/face comparison of 3 versus 10 subjects).

Under maximal use conditions following daily administration atsteady-state, the mean (SD) peak imiquimod serum concentrations areabout 0.323 (0.159) ng/mL, and the median time to peak concentration isabout 9 hours. Comparison of the mean C_(max) concentrations and themean trough concentrations indicates a relatively flatconcentration-time profile throughout the dosing interval. The observedelimination half-life averaged about 29.26 hours (range 9.72-84.06hours).

Steady state is believed to be achieved in this study by day 14 or thesecond week of daily dosing. Subjects in this study apply 2 packets (500mg of cream—250 mg/packet; 18.75 mg of imiquimod) daily for 3 weeks tothe entire face or balding scalp, and the mean peak serum imiquimodconcentration (C_(max)) is about 0.323 ng/mL. In a previous study of the5% imiquimod cream, subjects who receive 2 packets (500 mg of cream; 25mg of imiquimod) 3 times per week for 16 weeks to the scalp, the meanpeak serum imiquimod concentration (C_(max)) is 0.2 ng/mL. Subjects whoreceive six packets (1500 mg cream; 75 mg of imiquimod) 3 times per weekfor 16 weeks to the hand and forearms) have a C_(max) of 3.5 ng/ml.These results are shown below in Table 90.

TABLE 90 Mean Peak Serum Imiquimod Concentration in Adults FollowingAdministration of the Last Topical Dose of Aldara ® 5% Imiquimod CreamDuring Week 16 (Actinic Keratosis) Amount of Aldara ® 5% Mean peak serumimiquimod Imiquimod Cream applied concentration [C_(max)] 12.5 mg (1packet) 0.1 ng/mL   25 mg (2 packets) 0.2 ng/mL   75 mg (6 packets) 3.5ng/mL Source: Current Aldara ® Package Insert: Section 12.3Pharmacokinetics: Table 10

Pharmacokinetic data are available from three studies of patients withAK, one using the 3.75% imiquimod formulation of Example 23 (StudyGW01-0706), and two studies using the marketed Aldara® 5% imiquimodcream formulation (Study 1520-IMIQ and Study 1402-IMIQ). The dosage,treatment duration, application site and application area in thesestudies is summarized in Table 91.

TABLE 91 Summary of Dosage, Application Site, and Treated Surface Areafor Studies GW01-0706, 1520-IMIQ, and 1402-IMIQ Study Weekly Dose Dosage(imiquimod) Duration N^(a) Site Area Study GW01-0706 (3.75% imiquimodcream) 2 packets (18.75 mg) 131.25 mg   21 days 17 Face or Scalp 200 cm²daily Study 1520-IMIQ (5% imiquimod cream) 6 packets (75 mg) 2 x 150 mg16 wks^(d) 13 NS >25% of weekly BSA Study 1402-IMIQ (5% imiquimod cream)1 packet (12.5 mg) 3 x 37.5 mg  16 wks 23 Face  25 cm² weekly 2 packets(25 mg) 3 x  75 mg 16 wks 11 Scalp >25 cm² weekly 6 packets (75 mg) 3 x225 mg 16 wks 24 Hands/Arms^(b) NS^(c) weekly NS = not specified; BSA =Body surface area ^(a)Number of subjects in PK population atsteady-state ^(b)Applied to dorsal surface of forearms and hands, 3packets applied to each side ^(c)Not specified; estimated in the rangeof 300-400 cm² based on the protocol description ^(d)Data from one16-week treatment cycle, subjects could receive up to 3 cycles oftreatment over 18 months.

While studies 1402-IMIQ and GW01-0706 are primarily pharmacokineticstudies, the data from Study 1520-IMIQ is a large long-term safety trial(551 subjects enrolled), and the pharmacokinetic data comes from subsetof subjects representing a cohort receiving maximal exposure toimiquimod (6 packets of 5% cream applied twice weekly to >25% of theirbody surface area). Subjects in this study could participate in up tothree 16-week treatment cycles during the 18-month study. In Study1520-IMIQ, 71.9% of subjects (396 of 551) in the safety population havecompleted the trial. Subjects in the safety population average 466.9days in the study and apply an estimated average of 214.6 packets ofstudy drug (2682.5 mg of imiquimod). At study initiation, the medianprescribed dose is about 3.3 packets twice weekly, and 380 of 551subjects (69%) have received a dose of 3 or more packets twice weekly,and 182 subjects have received the maximal exposure of 6 packets twiceweekly.

Based on the total amount of drug administered during one week oftreatment, the weekly dose of the an 3.75% imiquimod lower dosagestrength formulation of Example 23 and the novel two week 2-cycle dosageregimen (2 packets daily or 131.25 mg imiquimod weekly) is similar tothe weekly dose that was used in the 1520-IMIQ study, and falls betweenthe two higher doses used in Study 1402-IMIQ. In addition, the novel twoweek 2-cycle dosage regimen treats a larger surface area (about 200 cm²)than the previously approved regimens for AK on the face and baldingscalp (25 cm²). Systemic exposure at steady-state is summarized in Table92.

TABLE 92 Summary of Systemic Exposure at Steady-State FollowingAdministration of 3.75% or 5% Imiquimod Cream [Mean(SD) Serum ImiquimodCmax and AUCss] Cmax (ng/mL) AUC (ng · hr/mL) Mean (SD) Ratio^(a) Mean(SD) Ratio^(a) Study GW01-0706 2 pkts (18.75 mg) daily to face/scalp0.323 (0.159) 5.974 (3.088) Study 1520-IMIQ^(b) 6 pkts (75 mg) 2 xweekly to >25% BSA 0.958 (1.18) 2.96 24.3 (26.9) 4.07 Study 1402-IMIQ 1pkts (12.5 mg) 3x/week to face 0.120 (0.0629) 0.37 2.06 (1.70) 0.34 2pkts (25 mg) 3x/week to scalp 0.214 (0.0968) 0.66 4.89 (4.41) 0.82 6pkts (75 mg) 3x/week to hand/forearms^(c)  1.35 (0.841) 4.18 29.1 (17.1)4.87 6 pkts (75 mg) 3x/week to hand/forearms^(d)  3.53 (6.52) 10.92 55.4(76.0) 9.27 Pkts = packets; BSA = Body surface area ^(a)5% imiquimodregimen/3.75% imiquimod regimen ^(b)Month 4 data ^(c)Data from Harrisonet al, 2004¹ (rejecting outliers that were >5X the SD of theirrespective means) ^(d)Data from the 1402-IMIQ² report that includesoutliers

The mean C_(max) and AUC in Study GW01-0706 at steady state aresubstantially lower than those that are observed followingadministration of the high dose used in the large safety trial (6packets, 75 mg, twice weekly, Study 1520-IMIQ). Based on these results,it is believed that the novel treatment regimen, i.e., an 3.75%imiquimod lower dosage strength formulation of Example 23 applied dailyin a two week 2-cycle dosage regimen (2 packets daily or 131.25 mgimiquimod weekly) has about an 3- to 4-fold safety margin for systemicexposure relative to the high-dose exposure in Study 1520-IMIQ. Thus,these results indicate that the intended dose of an 3.75% imiquimodcream product of Example 23 has less systemic exposure than what isobserved in the high dose group for the 5% imiquimod cream product inthe long-term safety Study 1520-IMIQ.

Pharmacokinetic profiles were obtained following single-dose andrepeat-dose administration of 3.75% imiquimod cream in Study GW01-0706(see Table 89 above). The mean (SD) accumulation ratios that arecalculated from C_(max) and AUC₀₋₂₄ are about 2.810 (1.514) and about3.873 (2.153), respectively. The mean effective half-life foraccumulation is about 55.3 hours and the mean observed eliminationhalf-life is about 29.3 hours on Day 21. Analysis of troughconcentrations over time indicate that steady-state conditions areachieved between Day 7 and Day 14.

In summary, the amount of imiquimod that is absorbed into systemiccirculation after topical application of an imiquimod 3.75% cream ofExample 23 to the face and/or scalp once daily for up to 21 days is low;peak and total serum imiquimod concentrations are increased by about 3to 4 fold between Day 1 and Day 21. Steady state is achieved by Day 14.C_(max) and AUC₀ ₂₄ on Day 21 appear to be similar in female and malesubjects and lower in male subjects who apply an imiquimod 3.75% creamof Example 23 to balding scalp rather the face.

Thus, the mean peak serum imiquimod concentration that is observed withthe daily application of the 3.75% imiquimod product (about 0.323 ng/mL)is within the mean peak serum imiquimod concentrations previouslyobserved with Aldara® 5% imiquimod cream.

Example 26 Meta-Analysis—Efficacy, Adverse Events, Local Skin Reactionsand Rest Periods

A meta analysis is conducted across the four clinical studies describedin Example 24. Data for Aldara® 5% imiquimod cream is displayed forcomparative purposes. See, e.g., FIGS. 25-30. Of course, the Aldara®data concerned much smaller size treatment areas and a smaller number ofAK lesions per treatment than the clinical studies that are described inExample 24.

Turning now to FIGS. 25 and 25A, they show the pooled actinic keratosislesion clearance rates, i.e., complete and partial clearance rates forthe 2.5% and 3.75% imiquimod formulations of Example 23 that are used inthe short duration therapies (2×2×2 weeks and 3×3×3 weeks), are about asequally effective as the Aldara® 5% imiquimod cream treatment, eventhough Aldara® was applied twice a week for 16 weeks on treatment areasno greater than about 25 cm² and to no more than between about 4 and 8AK lesions.

In FIG. 26, it shows the complete clearance rates for the 2.5% and 3.75%imiquimod formulations of Example 23, that are used in the shortduration therapies, i.e., 2×2×2 weeks and 3×3×3 weeks, are about asequally effective as the Aldara® 5% imiquimod cream treatment, eventhough Aldara® was applied twice a week for 16 weeks on treatment areasno greater than about 25 cm² and to no more than between about 4 and 8AK lesions.

In FIG. 27, it shows the partial clearance rates for the 2.5% and 3.75%imiquimod formulations of Example 23, that are used in the shortduration therapies, i.e., 2×2×2 weeks and 3×3×3 weeks, are about asequally effective as the Aldara® 5% imiquimod cream treatment eventhough Aldara® was applied twice a week for 16 weeks on treatment areasno greater than about 25 cm² and to no more than between about 4 and 8AK lesions.

In FIGS. 28 and 28A-B, an adverse events comparison is shown between the2.5% and 3.75% imiquimod formulations of Example 23 that are used in theshort duration therapies, i.e., 2×2×2 and 3×3×3 weeks, and the Aldara®5% imiquimod cream treatment that are used twice a week for 16 weeks ontreatment areas no greater than about 25 cm² and no more than betweenabout 4 and 8 AK lesions, to treat actinic keratosis. As depicted inFIGS. 28 and 28A-B, there is a higher percentage of application sitereactions and upper respiratory infections with the Aldara® 5% imiquimodcream treatment than with the low dosage strength 2.5% and 3.75%imiquimod formulations that are used in the short duration therapies,i.e., 2×2×2 and 3×3×3 weeks, even though the 2.5% and 3.75% imiquimodformulations of Example 23 are applied daily on treatment areas muchgreater than 25 cm².

In FIG. 29, it shows the incidence of severe local skin reactionserythema for the 2.5% and 3.75% imiquimod formulations of Example 23that are used in the 2×2×2 week short duration therapy are comparable tothe Aldara® 5% imiquimod cream treatment, but higher for the 3×3×3 weektherapy.

In FIG. 30, it shows the incidence of rest periods for the 2.5% and3.75% imiquimod formulations of Example 23 that are used in the 2×2×2week short duration therapy are lower than the Aldara® 5% imiquimodcream treatment, but higher for the 3×3×3 week therapy.

Example 27 A Comparison Between the Four Clinical Studies Described inExample 24 and Aldara®

A comparative analysis is conducted across the four clinical studiesdescribed in Example 24 and Aldara®. See, e.g., FIGS. 28, 28A-B and36-42. As previously indicated, treatment with Aldara® concerns muchsmaller size treatment areas and a smaller number of AK lesions pertreatment than the clinical studies that are described in Example 24.

As to FIGS. 28 and 28A-B, see Example 27.

Turning now to FIGS. 36 and 36A, the pooled percent of completeclearance rates for the 2.5% and 3.75% imiquimod formulations of Example23, that are used in the 2×2×2 weeks studies, and the 3×3×3 weeksstudies of Example 24, are displayed. Results across treatment regimens(2 week or 3 week treatment cycles) are comparable. A dose responsebetween 2.5% and 3.75% imiquimod formulations of Example 23 is evidentirrespective of regimen (2 week or 3 week treatment cycles).

Turning now to FIGS. 37 and 37A, the pooled percent of partial completeclearance rates for the 2.5% and 3.75% imiquimod formulations of Example23, that are used in the 2×2×2 weeks studies, and the 3×3×3 weeksstudies of Example 24, are displayed. Results across treatment regimens(2 week or 3 week treatment cycles) are comparable. A dose responsebetween 2.5% and 3.75% imiquimod formulations of Example 23 is evidentirrespective of regimen (2 week or 3 week treatment cycles).

Turning now to FIGS. 38 and 38A, the pooled percent of AK lesion median% reduction for the 2.5% and 3.75% imiquimod formulations of Example 23,that are used in the 2×2×2 weeks studies, and the 3×3×3 weeks studies ofExample 24, are displayed. Results across treatment regimens (2 week or3 week treatment cycles) are comparable. A dose response between 2.5%and 3.75% imiquimod formulations of Example 23 is evident irrespectiveof regimen (2 week or 3 week treatment cycles).

Turning now to FIG. 39, they show that the percent of subjects who tookat least one rest period during treatment for the 2.5% and 3.75%imiquimod formulations of Example 23, that are used in the 2×2×2 weeksstudies of Example 24, are less than those taken with Aldara® 5%imiquimod cream.

Turning now to FIG. 39A, the selected safety parameters for the combined2×2×2 or 3×3×3 studies show that the safety events are less favorable inthe 3×3×3 studies than the 2×2×2 studies.

Turning now to FIG. 40, it shows the percent of local skin reactions(LSRs) of subjects with severe LSRs for the 2.5% and 3.75% imiquimodformulations of Example 23, that is used in the 2×2×2 week studies ofExample 24. Overall, the incidence rates for severe LSRs are relativelylow, and as for Aldara® 5% imiquimod cream, the most common severe LSRis erythema.

Turning now to FIG. 41, it shows the incidence of adverse events ofsubjects for the 2.5% and 3.75% imiquimod formulations of Example 23,that is used in the 2×2×2 week studies of Example 24. The most commonadverse event is application site reactions which occurs at a lower ratethan Aldara® 5% imiquimod cream.

Turning now to FIG. 41A, it shows the incidence of treatment-relatedadverse events of subjects for the combined 2×2×2 or 3×3×3 studies. Thisshows that the incidence of adverse events are less favorable in the3×3×3 studies than the 2×2×2 studies.

Turning now to FIG. 42, it shows the benefit/risk analysis for both (1)the 2.5% and 3.75% imiquimod formulations of Example 23, that are usedin the 2×2×2 week studies of Example 24, and (2) the Aldara® 5%imiquimod cream, to treat actinic keratosis. As is shown, the 3.75%imiquimod formulation provides incremental efficacy benefit to the 2.5%imiquimod formulation as defined by results for complete clearance,partial clearance and median percent reductions. The 3.75% imiquimodformulation provides comparable efficacy to Aldara® 5% imiquimod creamas defined by partial clearance and median percent reductions notwithstanding the differences in treatment area size and baseline numbersof AK lesions in the studies of the 3.75% and 5% imiquimod formulations.As to risk, the incidences of severe erythema and the incidences of restperiods among the 2.5%, 3.75% and 5% (Aldara®) imiquimod formulationsare generally similar (that is within approximately 10% of each other).As noted with the assessment of benefits, these results are notwithstanding the differences in treatment area size and baseline numbersof AK lesions in the studies of the 2.5%, 3.75% and 5% imiquimodformulations. The third measure of risk, that is incidence ofapplication site reactions, shows low incidence rates for both the 2.5%and 3.75% imiquimod formulations and a minimum 3-fold higher incidencerate with the Aldara® 5% imiquimod cream formulation.

Example 28 Eight Individual Clinical Cases—Four Individual Two Week,2-Cycle Clinical Cases and Four Individual Three Week, 2-Cycle ClinicalCases

This Example 28 is directed to eight clinical cases wherein subjectsdiagnosed with actinic keratosis are treated with either 2.5% or 3.75%low dosage strength imiquimod formulations of Example 23 in accordancewith either a two-cycle, 2 week on×2 week off×2 week on treatmentregimen or a two-cycle, 3 week on×3 week off×3 week on treatmentregimen, as described herein. See, e.g., FIGS. 43-50 for a summary ofresults.

According to the clinical case summarized in FIG. 43, a 39 year oldwhite male has an AK lesion count of 11 on his balding scalp attreatment initiation. Consistent with the present invention, the fullbalding scalp is treated daily with a single dose of a 2.5% imiquimodformulation of Example 23. The 2.5% imiquimod formulation is packaged inindividual packets in an amount of 250 mg/packet. The number of averagepackets that are used by this 39 year old white male for each individualdaily dose is 1.25 packets. During the two-cycle, 2×2×2 weeks, treatmentperiod, this 39 year old white male neither misses a dose nor takes arest period.

Referring now to FIG. 43, the 39 year old white male is treated asfollows: during the first cycle of treatment, one dose (1.25 packets onaverage) of the 2.5% imiquimod formulation is applied to his fullbalding scalp once per day for 14 days; during the next 14 days,treatment is suspended; during the second cycle of treatment, treatmentis carried out identical to the treatment that is used during the firstcycle. At the end of the second cycle, the 39 year old white male ismonitored for an additional 8 weeks. During the entire 14 weeks, the 39year old white male is monitored for total or partial clearance, localskin reactions, including erythema, and adverse events at (a) baseline,(b) week 2, (c) week 6, (d) week 10, and (e) week 14.

In still referring to FIG. 43, at baseline before therapy, there is anAK lesion count of 11 and a local skin reaction (erythema) score of 0.At week 2, the AK lesion count is IND, but there is a local skinreaction erythema score of 2. At week 6, the AK lesion count remainsIND, but the local skin reaction erythema score is reduced to 1. At week14, the AK lesion count remains 0 (total clearance) and the local skinreaction erythema score returns to normal or baseline score.Lymphadenopathy is reported as a related adverse event.

Thus, this clinical case as summarized in FIG. 43, demonstrates efficacywithout treatment limiting local skin reactions or adverse events andfurther demonstrates that total or complete clearance is achieved with a2.5% imiquimod formulation of Example 23 when applied to the fullbalding scalp of a subject diagnosed with actinic keratosis following a2 cycle, 2×2×2 weeks, treatment period. This Example 28, as described inFIG. 43, also demonstrates the unique bimodal or camelback pattern as tothe local skin reaction score for erythema during the 2 cycle, 2×2×2weeks, treatment regimen, which is generated when following the shortdurations of therapy in accordance with the present invention.

According to the clinical case summarized in FIG. 44, a 74 year oldwhite male with Fitzpatrick skin type III has an AK lesion count of 8 onhis balding scalp at treatment initiation. Consistent with the presentinvention, the entire balding scalp is treated daily with a single doseof a 2.5% imiquimod formulation of Example 23. The 2.5% imiquimodformulation is packaged in individual packets in an amount of 250mg/packet. The number of average packets that are used by this 74 yearold white male for each individual daily dose is 2.0 packets. During thetwo-cycle, 2×2×2 weeks, treatment period, this 74 year old white maleneither misses a dose nor takes a rest period.

Referring now to FIG. 44, the 74 year old white male, is treated asfollows: during the first cycle of treatment, one dose (2.0 packets onaverage) of the 2.5% imiquimod formulation is applied to his fullbalding scalp once per day for 14 days; during the next 14 days,treatment is suspended; during the second cycle of treatment, treatmentis carried out identical to the treatment that is used during the firstcycle. At the end of the second cycle, the 74 year old white male ismonitored for an additional 8 weeks. During the entire 14 weeks, the 74year old white male is monitored for total or partial clearance, localskin reactions, including erythema, and adverse events at (a) baseline,(b) week 2, (c) week 4, (d) week 6, (e) week 10, and (f) week 14.

In still referring to FIG. 44, at baseline before therapy, there is anAK lesion count of 8 and a local skin reaction (erythema) score of 0, abaseline score of 0. At week 2, the AK lesion count is 19, but there isa local skin reaction erythema score of 2. At week 4, the AK lesioncount is reduced to 12, and the local skin reaction erythema score isreduced to 1. At week 6, the AK lesion count is increased to 33 and thelocal skin reaction erythema score is increased to 3. At week 10, the AKlesion count is reduced to 1 and the local skin reaction erythema scoreis now 0. At week 14, the AK lesion count is up to 2 (partial clearance)and the local skin reaction erythema score remains 0 or the same as thebaseline score. No adverse events are reported.

Thus, this clinical case as summarized in FIG. 44, demonstrates efficacywithout treatment limiting local skin reactions or adverse events andfurther demonstrates that a reduction in AK lesions (partial clearance)of about 75% from baseline is achieved with a 2.5% imiquimod formulationof Example 23 when applied to the full balding scalp of a subjectdiagnosed with actinic keratosis following a 2 cycle, 2×2×2 weeks,treatment period. This Example 28, as described in FIG. 44, is anotherexample of the unique bimodal or camelback pattern as to the local skinreaction score for erythema during the 2 cycle, 2×2×2 week, treatmentregimen, that is generated when following the short durations of therapyin accordance with the present invention.

According to the clinical case summarized in FIG. 45, a 66 year oldwhite female with Fitzpatrick skin type II has an AK lesion count of 9on her face at treatment initiation. Consistent with the presentinvention, the full face is treated daily with a single dose of a 3.75%imiquimod formulation of Example 23. The 3.75% imiquimod formulation ispackaged in individual packets in an amount of 250 mg/packet. The numberof average packets that are used by this 66 year old white female foreach individual daily dose is 1.26 packets. During the two-cycle, 2×2×2weeks, treatment period, this 66 year old white female neither missed adose on day 29 and took rest periods on days 11, 12, 13 and 14.

Referring now to FIG. 45, the 66 year old white female is treated asfollows: during the first cycle of treatment, one dose (1.26 packets onaverage) of the 3.75% imiquimod formulation is applied to her full faceonce per day for 14 days; during the next 14 days, treatment issuspended; during the second cycle of treatment, treatment is carriedout identical to the treatment that is used during the first cycle. Atthe end of the second cycle, the 66 year old white female is monitoredfor an additional 8 weeks. During the entire 14 weeks, the 66 year oldwhite female is monitored for total or partial clearance, local skinreactions, including erythema, and adverse events at (a) baseline, (b)week 2, (c) week 6 and (d) week 14.

In still referring to FIG. 45, at baseline before therapy, there is anAK lesion count of 9 and a local skin reaction (erythema) score of 0. Atweek 2, the AK lesion count is IND, but there is a local skin reactionerythema score of 2. At week 6, the AK lesion count remains IND, but thelocal skin reaction erythema score is reduced to 1. At week 14, the AKlesion count is 0 (total clearance) and the local skin reaction erythemascore remains at 1. Dizziness, facial stinging, sunburn (mild) arereported as related adverse events.

Thus, this clinical case as summarized in FIG. 45, demonstrates efficacywithout treatment limiting local skin reactions or adverse events andfurther demonstrates that total clearance is achieved with a 3.75%imiquimod formulation of Example 23 when applied to the full face of asubject diagnosed with actinic keratosis following a 2 cycle, 2×2×2weeks, treatment period. This Example 28, as described in FIG. 45, alsodemonstrates the unique bimodal or camelback pattern as to the localskin reaction score for erythema during the 2 cycle, 2×2×2 weeks,treatment regimen, which is generated when following the short durationsof therapy in accordance with the present invention.

According to the clinical case summarized in FIG. 46, a 73 year oldwhite male with Fitzpatrick skin type II has an AK lesion count of 9 onhis face at treatment initiation. Consistent with the present invention,the full face is treated daily with a single dose of a 3.75% imiquimodformulation of Example 23. The 3.75% imiquimod formulation is packagedin individual packets in an amount of 250 mg/packet. The number ofaverage packets that are used by this 73 year old white male for eachindividual daily dose is 1.18 packets. During the two-cycle, 2×2×2weeks, treatment period, this 73 year old white male neither misses adose nor takes a rest period.

Referring now to FIG. 46, the 73 year old white male, is treated asfollows: during the first cycle of treatment, one dose (1.18 packets onaverage) of the 3.75% imiquimod formulation is applied to his full faceonce per day for 14 days; during the next 14 days, treatment issuspended; during the second cycle of treatment, treatment is carriedout identical to the treatment that is used during the first cycle. Atthe end of the second cycle, the 73 year old white male is monitored foran additional 8 weeks. During the entire 14 weeks, the 73 year old whitemale is monitored for total or partial clearance, local skin reactions,including erythema, and adverse events at (a) baseline, (b) week 2, (c)week 4, (d) week 6, (e) week 10, and (f) week 14.

In still referring to FIG. 46, at baseline before therapy, there is anAK lesion count of 9 and a local skin reaction (erythema) score of 0. Atweek 2, the AK lesion count is 22, but there is a local skin reactionerythema score of 3. At week 4, the AK lesion count is reduced to 3, andthe local skin reaction erythema score is reduced to 0. At week 6, theAK lesion count is increased to 5 and the local skin reaction erythemascore is increased to 2. At week 10, the AK lesion count is reduced to 2and the local skin reaction erythema score is now 0. At week 14, the AKlesion count remains at 2 (partial clearance) and the local skinreaction erythema score remains at 0 or the same as the baseline score.No adverse events are reported.

Thus, this clinical case as summarized in FIG. 46, further demonstratesefficacy without treatment limiting local skin reactions or adverseevents and further demonstrates that a reduction in AK lesions (partialclearance) of greater than about 75% from baseline is achieved with a3.75% imiquimod formulation of Example 23 when applied to the full faceof a subject diagnosed with actinic keratosis following a 2 cycle, 2×2×2weeks, treatment regimen. This Example 28, as described in FIG. 46, isanother example of the unique bimodal or camelback pattern as to thelocal skin reaction score for erythema during the 2 cycle, 2×2×2 weeks,treatment regimen, which is generated when following the short durationsof therapy in accordance with the present invention.

According to the clinical case summarized in FIG. 47, a 70 year oldwhite male has an AK lesion count of 10 on his face at treatmentinitiation. Consistent with the present invention, the full face istreated daily with a single dose of a 2.5% imiquimod formulation ofExample 23. The 2.5% imiquimod formulation is packaged in individualpackets in an amount of 250 mg/packet. The number of average packetsthat are used by this 70 year old white male for each individual dailydose is 2.0 packets. During the two-cycle, 3×3×3 weeks, treatmentperiod, this 70 year old white male neither misses a dose nor takes arest period.

Referring now to FIG. 47, the 70 year old white male is treated asfollows: during the first cycle of treatment, one dose (2.0 packets onaverage) of the 2.5% imiquimod formulation is applied to his full faceonce per day for 21 days; during the next 21 days, treatment issuspended; during the second cycle of treatment, treatment is carriedout identical to the treatment that is used during the first cycle. Atthe end of the second cycle, the 70 year old white male is monitored foran additional 8 weeks. During the entire 17 weeks, the 70 year old whitemale is monitored for total or partial clearance, local skin reactions,including erythema, and adverse events at (a) baseline, (b) week 3, (c)week 9, and (d) week 17.

In still referring to FIG. 47, at baseline before therapy, there is anAK lesion count of 10 and a local skin reaction (erythema) score of 1.At week 3, the AK lesion count is IND, but there is a local skinreaction erythema score of 3. At week 9, the AK lesion count increasesto 13, but the local skin reaction erythema score remains at 3. At week17, the AK lesion count is reduced to 5 (partial clearance) and thelocal skin reaction erythema score returns to 1, i.e., normal orbaseline score. No adverse events are recorded.

Thus, this clinical case as summarized in FIG. 47, demonstrates efficacywithout treatment limiting local skin reactions or adverse events andfurther demonstrates that partial clearance is achieved with a 2.5%imiquimod formulation of Example 23 when applied to the full face of asubject diagnosed with actinic keratosis following a 2 cycle, 3×3×3week, treatment regimen. This Example 28, as described in FIG. 47, alsodemonstrates the unique bimodal or camelback pattern as to the localskin reaction score for erythema during the 2 cycle, 3×3×3 weeks,treatment regimen, which is generated when following the short durationsof therapy in accordance with the present invention.

According to the clinical case summarized in FIG. 48, a 65 year oldwhite female has an AK lesion count of 7 on her face at treatmentinitiation. Consistent with the present invention, the full face istreated daily with a single dose of a 2.5% imiquimod formulation ofExample 23. The 2.5% imiquimod formulation is packaged in individualpackets in an amount of 250 mg/packet. The number of average packetsthat are used by this 65 year old white female for each individual dailydose is 1.69 packets. During the two-cycle, 3×3×3 weeks, treatmentperiod, this 65 year old white female neither misses a dose nor takes arest period.

Referring now to FIG. 48, the 65 year old white female is treated asfollows: during the first cycle of treatment, one dose (1.69 packets onaverage) of the 2.5% imiquimod formulation is applied to her full faceonce per day for 21 days; during the next 21 days, treatment issuspended; during the second cycle of treatment, treatment is carriedout identical to the treatment that is used during the first cycle. Atthe end of the second cycle, the 65 year old white female is monitoredfor an additional 8 weeks. During the entire 17 weeks, the 65 year oldwhite female is monitored for total or partial clearance, local skinreactions, including erythema, and adverse events at (a) baseline, (b)week 3, (c) week 9, and (d) week 17.

In still referring to FIG. 48, at baseline before therapy, there is anAK lesion count of 7 and a local skin reaction (erythema) score of 1. Atweek 3, the AK lesion count is 1, but the local skin reaction erythemascore remains at 1. At week 9, both the AK lesion count and the localskin reaction erythema score are reduced to 0. At week 17, the AK lesioncount remains at 0 (complete clearance) and the local skin reactionerythema score remains at 0, i.e., below normal or baseline score. Alladverse events that are recorded are unrelated.

Thus, this clinical case as summarized in FIG. 48, demonstrates efficacywithout treatment limiting local skin reactions or adverse events andfurther demonstrates that complete clearance is achieved with a 2.5%imiquimod formulation of Example 23 when applied to the full face of asubject diagnosed with actinic keratosis following a 2 cycle, 3×3×3weeks, treatment regimen. This Example 28, as described in FIG. 48, alsodemonstrates the unique bimodal or camelback pattern as to the localskin reaction score for erythema during the 2 cycle, 3×3×3 week,treatment regimen, which is generated when following the short durationsof therapy in accordance with the present invention.

According to the clinical case summarized in FIG. 49, a 79 year oldwhite male has an AK lesion count of 14 on his face at treatmentinitiation. Consistent with the present invention, the full face istreated daily with a single dose of a 3.75% imiquimod formulation ofExample 23. The 3.75% imiquimod formulation is packaged in individualpackets in an amount of 250 mg/packet. The number of average packetsthat are used by this 79 year old white male for each individual dailydose is 1.14 packets. During the two-cycle, 3×3×3 week, treatmentperiod, this 79 year old white male neither misses a dose nor takes arest period.

Referring now to FIG. 49, the 79 year old white male is treated asfollows: during the first cycle of treatment, one dose (1.14 packets onaverage) of the 3.75% imiquimod formulation is applied to his full faceonce per day for 21 days; during the next 21 days, treatment issuspended; during the second cycle of treatment, treatment is carriedout identical to the treatment that is used during the first cycle. Atthe end of the second cycle, the 79 year old white male is monitored foran additional 8 weeks. During the entire 17 weeks, the 79 year old whitemale is monitored for total or partial clearance, local skin reactions,including erythema, and adverse events at (a) baseline, (b) week 3, (c)week 9 and (d) week 17.

In still referring to FIG. 49, at baseline before therapy, there is anAK lesion count of 14 and a local skin reaction (erythema) score of 1.At week 3, the AK lesion count is up to 16, and the local skin reactionerythema score is increased to 3. At week 9, however, the AK lesioncount falls to 6 and local skin reaction erythema score is reduced to 2.At week 17, the AK lesion count is 0 (total or complete clearance) andthe local skin reaction erythema score falls to 0, below normal orbaseline. No adverse events are reported.

Thus, this clinical case as summarized in FIG. 49, demonstrates efficacywithout treatment limiting local skin reactions or adverse events andfurther demonstrates that total or complete clearance is achieved with a3.75% imiquimod formulation of Example 23 when applied to the full faceof a subject diagnosed with actinic keratosis following a 2 cycle, 3×3×3week, treatment regimen. This Example 28, as described in FIG. 49, alsodemonstrates the unique bimodal or camelback pattern as to the localskin reaction score for erythema during the 2 cycle, 3×3×3 weeks,treatment regimen, which is generated when following the short durationsof therapy in accordance with the present invention.

According to the clinical case summarized in FIG. 50, a 78 year oldwhite male has an AK lesion count of 8 on his balding scalp at treatmentinitiation. Consistent with the present invention, the entire baldingscalp is treated daily with a single dose of a 3.75% imiquimodformulation of Example 23. The 3.75% imiquimod formulation is packagedin individual packets in an amount of 250 mg/packet. The number ofaverage packets that are used by this 78 year old white male for eachindividual daily dose is 2.0 packets. During the two-cycle, 3×3×3 weeks,treatment period, this 78 year old white male neither misses a dose nortakes a rest period.

Referring now to FIG. 50, the 78 year old white male, is treated asfollows: during the first cycle of treatment, one dose (2.0 packets onaverage) of the 3.75% imiquimod formulation is applied to his fullbalding scalp once per day for 21 days; during the next 21 days,treatment is suspended; during the second cycle of treatment, treatmentis carried out identical to the treatment that is used during the firstcycle. At the end of the second cycle, the 78 year old white male ismonitored for an additional 8 weeks. During the entire 17 weeks, the 78year old white male is monitored for total or partial clearance, localskin reactions, including erythema, and adverse events at (a) baseline,(b) week 3, (c) week 9, and (d) week 17.

In still referring to FIG. 50, at baseline before therapy, there is anAK lesion count of 8 and a local skin reaction (erythema) score of 1. Atweek 3, the AK lesion count is IND, but there is a local skin reactionerythema score of 3. At week 9, the AK lesion count is up to 2, but thelocal skin reaction erythema score is reduced to 1. At week 17, both theAK lesion count and the local skin reaction erythema score are at 0. Alladverse events that incur are recorded as unrelated to treatment.

Thus, this clinical case as summarized in FIG. 50, further demonstratesefficacy without treatment limiting local skin reactions or adverseevents and further demonstrates that complete clearance is achieved witha 3.75% imiquimod formulation of Example 23 when applied to the fullbalding scalp of a subject diagnosed with actinic keratosis following a2 cycle, 3×3×3 weeks, treatment regimen. This Example 28, as describedin FIG. 50, is another example of the unique bimodal or camelbackpattern as to the local skin reaction score for erythema during the 2cycle, 3×3×3, treatment regimen, which is generated when following theshort durations of therapy in accordance with the present invention. InExample 23 herein above, formulations 126 and 182, wherein the fattyacid is a, are the formulations that are used in Examples 24-28 and inFIGS. 1-54 discussed and described herein above. In addition, is aformulations 126 and 182 pass the PET tests when stored at about 40° C.for about 3 months.

The complete disclosures of the patents, patent documents, andpublications cited herein are incorporated by reference in theirentireties as if each were individually incorporated. In case ofconflict, the present specification, including definitions, shallcontrol. Various modifications and alterations to this invention willbecome apparent to those skilled in the art without departing from thescope and spirit of this invention. Illustrative embodiments andexamples are provided as examples only and are not intended to limit thescope of the present invention. The scope of the invention is limitedonly by the claims set forth as follows.

1. A pharmaceutical composition for topical administration comprising:(a) about 3.75% by weight of imiquimod; and (b) a pharmaceuticallyacceptable vehicle; wherein the pharmaceutical composition has doseproportionate release rates as to both the release rates of theimiquimod and the total amount of imiquimod released, relative to theAldara® 5% imiquimod cream.
 2. The pharmaceutical composition of claim1, wherein the pharmaceutically acceptable vehicle comprises a fattyacid.
 3. The pharmaceutical composition of claim 2, wherein the fattyacid is selected from the group consisting of palmitic acid, linoleicacid, stearic acid, isostearic acid, unrefined oleic acid, super refinedoleic acid and mixtures thereof.
 4. The pharmaceutical composition ofclaim 2, wherein the fatty acid is isostearic acid.
 5. Thepharmaceutical composition of claim 2, wherein the fatty acid is oleicacid.
 6. The pharmaceutical composition of claim 1, wherein thecomposition is selected from a group consisting of the 3.75% imiquimodformulations in Table
 9. 7. The pharmaceutical composition of claim 2,wherein the fatty acid is present in an amount of between about 5% and30% by weight.
 8. The pharmaceutical composition of claim 2, wherein thefatty acid is present in an amount of about 20% by weight.
 9. Thepharmaceutical composition of claim 1, wherein a generic pharmaceuticalcomposition formulated with imiquimod in an amount of about 3.75% byweight is bioequivalent to said pharmaceutical composition.
 10. Thepharmaceutical composition of claim 1, wherein a generic pharmaceuticalcomposition formulated with imiquimod in an amount of about 3.75% byweight is therapeutically equivalent to said pharmaceutical composition.11. The pharmaceutical composition of claim 1, wherein a genericpharmaceutical composition formulated with imiquimod in an amount ofabout 3.75% by weight is pharmaceutically equivalent to saidpharmaceutical composition.
 12. The pharmaceutical composition of claim1, wherein the pharmaceutical composition remains free of degradationproducts when stored at about 25° C./60% RH, about 30° C./65% RH andabout 40° C./75% RH over about one, about two, about three and about sixmonths and when analyzed at about 318 nm wavelength.
 13. Thepharmaceutical composition of claim 1, wherein the lower dosage strengthimiquimod formulation has an in-vivo serum profile selected from thegroup of pharmacokinetic characteristics consisting of: (a) a Day 21T_(max) of from about 4 hours to about 16 hours and preferably a meanT_(max) of about 7.4 hours with a standard deviation (“SD”) of about3.5, a median T_(max) of about 9 hours and a geometric mean T_(max) ofabout 6.6 hours and a coefficient of variation (“CV”) of about 48%; (b)a Day 21 C_(max) of from about 0.07 to about 0.6 ng/ml and preferably amean C_(max) of about 0.3 ng/ml with a standard deviation of about 0.16,a median C_(max) of about 0.35 and a geometric mean C_(max) of about0.27 ng/ml and a coefficient of variation of about 49%; (c) a Day 21T_(1/2) of from about 9.7 to about 84 hours and preferably a meanT_(1/2) of about 29.3 hours with a standard deviation of about 17, amedian T_(1/2) of about 25.6 hours and a geometric mean T_(1/2) of about26 hours and a coefficient of variation of about 58%; (d) a Day 21AUC₀₋₂₄ of from about 1.1 to about 12 ng·hr/ml and preferably a meanAUC₀₋₂₄ of about 6 ng·hr/ml with a standard deviation of about 3, amedian AUC₀₋₂₄ of about 7 ng·hr/ml and a geometric mean AUC₀₋₂₄ of about5 ng·hr/ml and a coefficient of variation of about 52%; (e) a Day 21 λzof from about 0.008 hr⁻¹ to about 0.07 hr⁻¹ and preferably a mean λz ofabout 0.03 hr⁻¹ with a standard deviation of about 0.01, a median λz ofabout 25.6 hr⁻¹ and a geometric mean λz of about 0.03 hr⁻¹ and acoefficient of variation of about 49%; (f) a Day 21 C_(min) of fromabout 0.06 to about 0.4 and preferably a mean C_(min) of about 0.20 withan SD of about 0.11, a median C_(min) of about 0.19 and a geometric meanC_(min) of about 0.17 and a coefficient of variation of about 55%; (g)at Day 14/7 (a ratio of the trough concentration at Day 14 over thetrough concentration at Day 7), a trough concentration geometric meanratio of about 1.09 with a 90% confidence interval (“CI”) within a rangeof between about 0.8 and about 1.5; (h) at Day 21/14 (a ratio of thetrough concentration at Day 21 over the trough concentration at Day 14),a trough concentration geometric mean ratio of about 1.33 with a 90%confidence interval (“CI”) within a range of between about 0.9 and about1.9; (i) at Day 22/21 (a ratio of the trough concentration at Day 22over the trough concentration at Day 21) a trough concentrationgeometric mean ratio of about 0.93 with a 90% confidence interval (“CI”)within a range of between about 0.6 and about 1.3; (j) a mean peakimiquimod serum concentration of about 0.323 ng/ml at Day 21; (k) a Day21 RAUC of from about 1 to about 7 and preferably a mean RAUC of about 4with a standard deviation of about 2, a median RAUC of about 3.5 and ageometric mean RAUC of about 3.3 and a coefficient of variation of about56%; (l) a Day 21 RC_(max) of from about 0.5 to about 5 and preferably amean RC_(max) of about 3 with a standard deviation of about 1.5, amedian RC_(max) of about 2.7 and a geometric mean RC_(max) of about 2.4and a coefficient of variation of about 54%; (m) a Day 21 Lλz_(eff) offrom about 0.006 hr⁻¹ to about 0.08 hr⁻¹ and preferably a mean Lλz_(eff)of about 0.02 hr⁻¹ with a standard deviation of about 0.02, a medianLλz_(eff) of about 0.01 hr⁻¹ and a geometric mean Lλz_(eff) of about0.16 hr⁻¹ and a coefficient of variation of about 97%; and (n) a Day 21T^(1/2) _(eff) of from about 8 hr to about 110 hr and preferably a meanT^(1/2) _(eff) of about 55 hr with a standard deviation of about 36, amedian T^(1/2) _(eff) of about 50 hr and a geometric mean T^(1/2) _(eff)of about 42 hr⁻¹ and a coefficient of variation of about 66%.
 14. Apharmaceutical composition for topical administration comprising: (a)about 3.75% by weight of imiquimod; and (b) a pharmaceuticallyacceptable vehicle comprising a fatty acid, cetyl alcohol, stearylalcohol, white petrolatum, polysorbate 60, sorbitan monostearate,glycerin, xanthan gum, purified water, benzyl alcohol, methylparaben,and propylparaben; wherein the pharmaceutical composition has doseproportionate release rates as to both the release rates of theimiquimod and the total amount of imiquimod released, relative to theAldara® 5% imiquimod cream.
 15. An imiquimod formulation for topicaladministration for treating actinic keratosis, said imiquimodformulation comprising: about 3.75% by weight of 1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine (imiquimod), and apharmaceutically acceptable vehicle for the imiquimod, which vehiclecomprises a fatty acid, for application to a treatment area once a dayfor a short duration of therapy to topically or transdermally deliver aneffective amount of imiquimod to the treatment area to treat actinickeratosis; wherein the pharmaceutical composition has dose proportionaterelease rates as to both the release rates of the imiquimod and thetotal amount of imiquimod released, relative to the Aldara® 5% imiquimodcream.
 16. The pharmaceutical composition of claim 14, wherein the fattyacid is isostearic acid.
 17. The imiquimod formulation of claim 15,wherein the fatty acid is isostearic acid.
 18. The imiquimod formulationof claim 15, wherein the fatty acid is oleic acid.
 19. Thepharmaceutical composition of claim 1, wherein the pharmaceuticalcomposition is a cream.
 20. The pharmaceutical composition of claim 14,wherein the imiquimod formulation is a cream.